Reduced overhead error detection code design for decoding a codeword

ABSTRACT

Methods, systems, and devices for wireless communications are described. An encoder of a wireless device may receive a transport block (TB) for transmission and segment the transport block into a set of multiple, smaller data segments that respectively correspond to a plurality of code blocks of the TB. The encoder may generate a code block level (CB-level) error detection code (EDC) for a subset of the data segments. The encoder may generate a transport block-level (TB-level) EDC for the TB using the data segments. Each of the code blocks (CBs) may be of the same size and may include one of the data segments. A subset of the CBs may include a data segment from the subset of the data segments and one of the CB-level EDCs. The remaining CBs that are not part of the subset may include a remaining data segments and the TB-level EDC.

CROSS REFERENCE

The present application for patent is a continuation of U.S. patentapplication Ser. No. 16/763,304 by Xu et al., entitled “Reduced OverheadError Detection Code Design For Decoding A Codeword” filed May 12, 2020,which is a 371 national phase filing of International Patent ApplicationNo. PCT/CN2018/112208 TO Xu et al, entitled “Reduced Overhead ErrorDetection Code Design For Decoding A Codeword,” filed Oct. 26, 2018,which claims priority to International Patent Application No.PCT/CN2017/111321 to Xu et al., titled “Reduced Overhead Error DetectionCode Design for Decoding a Codeword,” filed Nov. 16, 2017, assigned tothe assignee hereof, which is expressly incorporated herein by referencein its entirety.

BACKGROUND

The following relates generally to wireless communication, and morespecifically to reduced overhead error detection code design fordecoding a codeword.

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, or power). Examples of suchmultiple-access systems include fourth generation (4G) systems such as aLong Term Evolution (LTE) systems or LTE-Advanced (LTE-A) systems, andfifth generation (5G) systems which may be referred to as New Radio (NR)systems. These systems may employ technologies such as code divisionmultiple access (CDMA), time division multiple access (TDMA), frequencydivision multiple access (FDMA), orthogonal frequency division multipleaccess (OFDMA), or discrete Fourier transform-spread-OFDM (DFT-S-OFDM).A wireless multiple-access communications system may include a number ofbase stations or network access nodes, each simultaneously supportingcommunication for multiple communication devices, which may be otherwiseknown as user equipment (UE).

In some wireless communications systems, data may be transmitted to atarget device according to a transport block (TB) arrangement, where aTB may include a plurality of code blocks (CBs). A transmitting devicemay generate and encode a TB for transmission to the target device via awireless channel. Hybrid automatic repeat request (HARQ) feedback is onetechnique of increasing the likelihood that a TB is successfullyreceived by the target device. HARQ may include a combination of errordetection (e.g., using a cyclic redundancy check (CRC)), forward errorcorrection (FEC), and retransmission (e.g., automatic repeat request(ARQ)). The target device for the data transmission may transmitacknowledgment (ACK) feedback for each TB that is successfully received,and negative-acknowledgment (NACK) feedback for each TB that is notsuccessfully received. Some wireless communications systems may settransmission latency specifications, or block error ratio (BLER)specifications, or both, for certain types of communications, such asultra-reliable low latency communications (URLLC). CRC overhead in a TBmay be significant in conventional systems, and conventional systems maybe unable to meet transmission latency specifications, or block errorratio (BLER) specifications, or both, for certain types ofcommunications.

SUMMARY

The described techniques relate to improved methods, systems, devices,or apparatuses that support techniques for reducing error detection codeoverhead. Generally, the described techniques reduce error detectioncode overhead by generating code block level (CB-level) error detectioncodes (EDCs) for a subset of code blocks (CBs) in a transport block (TB)and a TB-level EDC for the TB, and generating a codeword using theCB-level EDCs and the TB-level EDC. The reduced EDC overhead may improvedata throughput and reduce decoding latency at a receiver, and improvethe likelihood of meeting transmission latency specifications, or blockerror ratio (BLER) specifications, or both, for certain types ofcommunications, such as ultra-reliable low latency communications(URLLC).

In an example, an encoder of a wireless device may receive a TB fortransmission and segment the TB into a set of multiple, smaller datasegments. The encoder may generate a CB-level EDC for a subset of thedata segments, and the CB-level EDCs and the data segments may beincluded in respective CBs that each may be the same size (e.g., each CBincludes the same number of bits). The encoder may also generate atransport block-level (TB-level) EDC for the TB using the data segments.

A subset of the CBs may include a data segment from the subset of thedata segments and one of the CB-level EDCs. The remaining one or moreCBs that are not part of the subset may include a remaining one of thedata segments and the TB-level EDC. The CB that includes the TB-levelEDC may be the same length as the other CBs of the TB (e.g., CBs with adata segment and CB-level EDC). Based on each CB being the same length(e.g., including the same number of bits), the same codes may be appliedfor each CB, and a receiving device may use a common decoder for each CBof the TB.

Prior to communicating with the receiving device, the transmittingwireless device may signal to the receiving device a coding scheme beingused (e.g., polar code being used to encode a TB), and which subset ofthe CBs in the TB include the CB-level EDC, and which one or more CBs inthe TB includes the TB-level EDC. The transmitting wireless device maygenerate a codeword from the TB, the subset of the CB-level EDCs, andthe TB-level EDC. The transmitting wireless device may, for example,encode the TB, the subset of the CB-level EDCs, and the TB-level EDCaccording to a polar code to generate the codeword, and modulate thecodeword for transmission to the receiving device via a wirelesschannel.

The receiving device may receive, via the wireless channel, a signalthat includes the modulated codeword. The receiving device maydemodulate and decode the signal to obtain a candidate bit sequence,using, for example, a list decoding algorithm according to the samepolar code used to generate the codeword. The receiving device mayattempt to determine whether the candidate bit sequence passes each ofCB-level and TB-level error detection. If it passes, the receivingdevice may obtain the TB from the candidate bit sequence and determinethat the received TB is the same TB as sent by the transmitter.

To perform error detection, the receiving device may parse the candidatebit sequence into CBs and perform CB-level error detection on the subsetof the CBs that include the CB-level EDC. For example, the receivingdevice may obtain a data segment and a received CB-level EDC from aparticular CB, calculate a CB-level EDC from the data segment using thesame algorithm as applied by the transmitting device, and determinewhether the calculated CB-level EDC matches the received CB-level EDC.

If each data segment in the subset of CBs passes CB-level errordetection, the receiving device may then check the TB-level EDC. If theTB-level EDC fails, but each CB-level EDC passes, the receiving devicemay determine that only the data segment associated with the TB-levelEDC failed error detection, and the receiving device may request aretransmission of just the failed data segment.

If one or more of the CB-level EDCs fail error detection, the receivingdevice may request a retransmission of each data segment which failederror detection as well as the data segment in the CB that included theTB-level EDC. In some examples, the receiving device may perform anearly termination of decoding the TB-level EDC and corresponding datasegment based on a CB-level EDC failing error detection. Beneficially,the techniques described herein may reduce error detection overhead andreduce decoding complexity, to improve the likelihood of a communicationmeeting BLER and/or transmission latency specifications.

A method of wireless communication is described. The method may includesegmenting a transport block into a plurality of data segments,generating a CB-level EDC for each data segment of a subset of theplurality of data segments, generating a TB-level EDC based at least inpart on the plurality of data segments, generating a codeword based atleast in part on the plurality of data segments, the CB-level EDCs forthe subset of the plurality of data segments, and the TB-level EDC, andtransmitting the codeword via a wireless channel.

An apparatus for wireless communication is described. The apparatus mayinclude means for segmenting a transport block into a plurality of datasegments, means for generating a CB-level EDC for each data segment of asubset of the plurality of data segments, means for generating aTB-level EDC based at least in part on the plurality of data segments,means for generating a codeword based at least in part on the pluralityof data segments, the CB-level EDCs for the subset of the plurality ofdata segments, and the TB-level EDC, and means for transmitting thecodeword via a wireless channel.

Another apparatus for wireless communication is described. The apparatusmay include a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe operable to cause the processor to segment a transport block into aplurality of data segments, generate a CB-level EDC for each datasegment of a subset of the plurality of data segments, generate aTB-level EDC based at least in part on the plurality of data segments,generate a codeword based at least in part on the plurality of datasegments, the CB-level EDCs for the subset of the plurality of datasegments, and the TB-level EDC, and transmit the codeword via a wirelesschannel.

A non-transitory computer-readable medium for wireless communication isdescribed. The non-transitory computer-readable medium may includeinstructions operable to cause a processor to segment a transport blockinto a plurality of data segments, generate a CB-level EDC for each datasegment of a subset of the plurality of data segments, generate aTB-level EDC based at least in part on the plurality of data segments,generate a codeword based at least in part on the plurality of datasegments, the CB-level EDCs for the subset of the plurality of datasegments, and the TB-level EDC, and transmit the codeword via a wirelesschannel.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein, generating the codeword mayinclude encoding the plurality of data segments, the CB-level EDCs, andthe TB-level EDC using a polar code to obtain the codeword.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein, generating the CB-level EDCfor each data segment of the subset of the plurality of data segmentsmay include generating the CB-level EDC for each of the plurality ofdata segments other than an identified data segment of the plurality ofdata segments.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein may further include processes,features, means, or instructions for associating each data segment ofthe plurality of data segments with a respective code block of aplurality of code blocks, where an identified code block of theplurality of code blocks includes the identified data segment and theTB-level EDC.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein, each of the plurality of codeblocks other than the identified code block may include a respectivedata segment of the plurality of data segments other than the identifieddata segment and a respective CB-level EDC of the CB-level EDCs.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein, each of the CB-level EDCsincludes a first number of bits and the TB-level EDC includes a secondnumber of bits that differs from the first number of bits.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein, at least one code block of aplurality of code blocks includes the TB-level EDC and a data segment ofthe plurality of data segments that may have fewer bits than at leastone other data segment of the plurality of data segments.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein may further include processes,features, means, or instructions for receiving feedback indicating thatat least one data segment of the plurality of data segments did not passerror detection. Some examples of the method, apparatus, andnon-transitory computer-readable medium described herein may furtherinclude processes, features, means, or instructions for generating asecond codeword based at least in part on the at least one data segment.Some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein may further include processes,features, means, or instructions for transmitting the second codewordvia the wireless channel.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein may further include processes,features, means, or instructions for processing a sequence of bitsincluded in the feedback to determine which one or more of the pluralityof data segments passed error detection and which one or more of theplurality of data segments did not pass error detection.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein, each of the CB-level EDCs maybe a CB-level cyclic redundancy check (CRC) and the TB-level EDC may bea TB-level CRC.

A method of wireless communication is described. The method may includeprocessing a signal including a codeword to obtain a candidate bitsequence, segmenting the candidate bit sequence into a plurality of codeblocks that each includes a respective data segment of a plurality ofdata segments, identifying a first data segment of a first code block ofthe plurality of code blocks using a code block-level (CB-level) errordetection code of the first code block, identifying a second datasegment of a second code block of the plurality of code blocks using aCB-level error detection code of the second code block, generating atransport block (TB) by combining the first data segment and the seconddata segment, and performing a TB-level error detection determination ofthe first data segment and the second data segment of the TB block usinga TB-level error detection code.

An apparatus for wireless communication is described. The apparatus mayinclude a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe operable to cause the processor to process a signal including acodeword to obtain a candidate bit sequence, segment the candidate bitsequence into a plurality of code blocks that each includes a respectivedata segment of a plurality of data segments, identify a first datasegment of a first code block of the plurality of code blocks using acode block-level (CB-level) error detection code of the first codeblock, identifying a second data segment of a second code block of theplurality of code blocks using a CB-level error detection code of thesecond code block, generate a transport block (TB) by combining thefirst data segment and the second data segment, and perform a TB-levelerror detection determination of the first data segment and the seconddata segment of the TB block using a TB-level error detection code.

Another apparatus for wireless communication is described. The apparatusmay include means for processing a signal including a codeword to obtaina candidate bit sequence, segmenting the candidate bit sequence into aplurality of code blocks that each includes a respective data segment ofa plurality of data segments, identifying a first data segment of afirst code block of the plurality of code blocks using a codeblock-level (CB-level) error detection code of the first code block,identifying a second data segment of a second code block of theplurality of code blocks using a CB-level error detection code of thesecond code block, generating a transport block (TB) by combining thefirst data segment and the second data segment, and performing aTB-level error detection determination of the first data segment and thesecond data segment of the TB block using a TB-level error detectioncode.

A non-transitory computer-readable medium for wireless communication isdescribed. The non-transitory computer-readable medium may includeinstructions operable to cause a processor to process a signal includinga codeword to obtain a candidate bit sequence, segment the candidate bitsequence into a plurality of code blocks that each includes a respectivedata segment of a plurality of data segments, identify a first datasegment of a first code block of the plurality of code blocks using acode block-level (CB-level) error detection code of the first codeblock, identifying a second data segment of a second code block of theplurality of code blocks using a CB-level error detection code of thesecond code block, generate a transport block (TB) by combining thefirst data segment and the second data segment, and perform a TB-levelerror detection determination of the first data segment and the seconddata segment of the TB block using a TB-level error detection code.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein, performing the TB-level errordetection determination may include determining that the first datasegment and the second data segment passed error detection based atleast in part on determining that CB-level error detectiondeterminations associated with the first code block and the second codeblock and the TB-level error detection determination do not indicate anerror.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein, performing a TB-level errordetection determination may include setting the TB-level error detectiondetermination to indicate that an error was identified based at least inpart on determining that at least one of CB-level error detectiondeterminations associated with the first code block and the second codeblock indicates an error.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein may further include processes,features, means, or instructions for transmitting feedback indicatingthat at least one of the first data segment and the second data segmentdid not pass error detection based at least in part on CB-level errordetection determinations associated with the first code block and thesecond code block.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein, performing a TB-level errordetection determination may include determining that none of a set ofCB-level error detection determinations associated with the first codeblock and the second code block indicate an error, and performing anerror detection algorithm on the first data segment and the second datasegment to generate the TB-level error detection determination. In someexamples of the method, apparatus, and non-transitory computer-readablemedium described herein, performing the error detection algorithm mayinclude transmitting feedback indicating that the error detectionalgorithm detected a TB-level error. In some examples of the method,apparatus, and non-transitory computer-readable medium described herein,performing the error detection algorithm may include determining thatthe error detection algorithm did not detect a TB-level error, andtransmitting feedback indicating that the first data segment and thesecond data segment passed error detection. In some examples of themethod, apparatus, and non-transitory computer-readable medium describedherein, processing the signal comprising the codeword to obtain thecandidate bit sequence may include performing a list decoding algorithmto decode the codeword according to a polar code to generate thecandidate bit sequence.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein further include generating acalculated CB-level error detection code (EDC) for the first datasegment, obtaining a received CB-level EDC from the first code block,and comparing the calculated CB-level EDC and the received CB-level EDC,wherein CB-level error detection determination for the first code blockindicates whether the calculated CB-level EDC matches the receivedCB-level EDC. In some examples of the method, apparatus, andnon-transitory computer-readable medium described herein, performing theTB-level error detection determination may include generating acalculated TB-level error detection code (EDC) based at least in part onthe first data segment and the second data segment, obtaining a receivedTB-level EDC from the second code block, and comparing the calculatedTB-level EDC and the received TB-level EDC, wherein the TB-level errordetection determination indicates whether the calculated TB-level EDCmatches the received TB-level EDC.

A method of wireless communication is described. The method may includeprocessing a signal including a codeword to obtain a candidate bitsequence, segmenting the candidate bit sequence into a plurality of codeblocks that each includes a respective data segment of a plurality ofdata segments, generating a CB-level error detection determination foreach code block of a subset of the plurality of code blocks, generatinga TB-level error detection determination associated with the pluralityof data segments, and generating an error detection determinationassociated with the plurality of data segments based at least in part onthe CB-level error detection determinations and the TB-level errordetection determination.

An apparatus for wireless communication is described. The apparatus mayinclude means for processing a signal including a codeword to obtain acandidate bit sequence, means for segmenting the candidate bit sequenceinto a plurality of code blocks that each include a respective datasegment of a plurality of data segments, means for generating a CB-levelerror detection determination for each code block of a subset of theplurality of code blocks, means for generating a TB-level errordetection determination associated with the plurality of data segments,and means for generating an error detection determination associatedwith the plurality of data segments based at least in part on theCB-level error detection determinations and the TB-level error detectiondetermination.

Another apparatus for wireless communication is described. The apparatusmay include a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe operable to cause the processor to process a signal including acodeword to obtain a candidate bit sequence, segment the candidate bitsequence into a plurality of code blocks that each include a respectivedata segment of a plurality of data segments, generate a CB-level errordetection determination for each code block of a subset of the pluralityof code blocks, generate a TB-level error detection determinationassociated with the plurality of data segments, and generate an errordetection determination associated with the plurality of data segmentsbased at least in part on the CB-level error detection determinationsand the TB-level error detection determination.

A non-transitory computer-readable medium for wireless communication isdescribed. The non-transitory computer-readable medium may includeinstructions operable to cause a processor to process a signal includinga codeword to obtain a candidate bit sequence, segment the candidate bitsequence into a plurality of code blocks that each include a respectivedata segment of a plurality of data segments, generate a CB-level errordetection determination for each code block of a subset of the pluralityof code blocks, generate a TB-level error detection determinationassociated with the plurality of data segments, and generate an errordetection determination associated with the plurality of data segmentsbased at least in part on the CB-level error detection determinationsand the TB-level error detection determination.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein, generating the errordetection determination associated with the plurality of data segmentsmay include determining that the plurality of data segments passed errordetection based at least in part on determining that each of theCB-level error detection determinations and the TB-level error detectiondetermination do not indicate an error.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein, generating the TB-level errordetection determination may include setting the TB-level error detectiondetermination to indicate that an error was identified based at least inpart on determining that at least one of the CB-level error detectiondeterminations indicate an error.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein may further include processes,features, means, or instructions for transmitting feedback indicatingthat one or more of the plurality of data segments did not pass errordetection based at least in part on the CB-level error detectiondeterminations.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein, generating the TB-level errordetection determination may include determining that none of theCB-level error detection determinations indicate an error. Some examplesof the method, apparatus, and non-transitory computer-readable mediumdescribed herein may further include processes, features, means, orinstructions for performing an error detection algorithm on theplurality of data segments to generate the TB-level error detectiondetermination.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein, performing the errordetection algorithm may include transmitting feedback indicating thatthe error detection algorithm detected a TB-level error.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein, performing the errordetection algorithm may include determining that the error detectionalgorithm did not detect a TB-level error. Some examples of the method,apparatus, and non-transitory computer-readable medium described hereinmay further include processes, features, means, or instructions fortransmitting feedback indicating that the plurality of data segmentspassed error detection.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein, processing the signalincluding the codeword to obtain the candidate bit sequence may includeperforming a list decoding algorithm to decode the codeword according toa polar code to generate the candidate bit sequence.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein, generating the CB-level errordetection determination for each code block of the subset of theplurality of code blocks may include obtaining a first data segment ofthe plurality of data segments from a first code block of the pluralityof code blocks. Some examples of the method, apparatus, andnon-transitory computer-readable medium described herein may furtherinclude processes, features, means, or instructions for generating acalculated CB-level EDC for the first data segment. Some examples of themethod, apparatus, and non-transitory computer-readable medium describedherein may further include processes, features, means, or instructionsfor obtaining a received CB-level EDC from the first code block. Someexamples of the method, apparatus, and non-transitory computer-readablemedium described herein may further include processes, features, means,or instructions for comparing the calculated CB-level EDC and thereceived CB-level EDC, where the CB-level error detection determinationfor the first code block indicates whether the calculated CB-level EDCmatches the received CB-level EDC.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described herein, generating the TB-level errordetection determination may include generating a calculated TB-level EDCbased at least in part on the plurality of data segments. Some examplesof the method, apparatus, and non-transitory computer-readable mediumdescribed herein may further include processes, features, means, orinstructions for obtaining a received TB-level EDC from an identifiedcode block of the plurality of code blocks. Some examples of the method,apparatus, and non-transitory computer-readable medium described hereinmay further include processes, features, means, or instructions forcomparing the calculated TB-level EDC and the received TB-level EDC,where the TB-level error detection determination indicates whether thecalculated TB-level EDC matches the received TB-level EDC.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a wireless communications system thatsupports a reduced overhead error detection code (EDC) design fordecoding a codeword in accordance with aspects of the presentdisclosure.

FIG. 2 illustrates an example of a wireless communications system thatsupports a reduced overhead EDC design for decoding a codeword inaccordance with aspects of the present disclosure.

FIG. 3 illustrates an example of a wireless communications system thatsupports a reduced overhead EDC design for decoding a codeword inaccordance with aspects of the present disclosure.

FIG. 4 illustrates an example of an EDC design that supports a reducedoverhead EDC design for decoding a codeword in accordance with aspectsof the present disclosure.

FIG. 5 illustrates an example of an efficient EDC design wirelesscommunications system that supports a reduced overhead EDC design fordecoding a codeword in accordance with aspects of the presentdisclosure.

FIG. 6 illustrates an example of an efficient EDC design that supports areduced overhead EDC design for decoding a codeword in accordance withaspects of the present disclosure.

FIG. 7 illustrates an example of a process flow that supports a reducedoverhead EDC design for decoding a codeword in accordance with aspectsof the present disclosure.

FIGS. 8 through 10 show block diagrams of a device that supports areduced overhead EDC design for decoding a codeword in accordance withaspects of the present disclosure.

FIG. 11 illustrates a block diagram of a system including a UE thatsupports a reduced overhead EDC design for decoding a codeword inaccordance with aspects of the present disclosure.

FIG. 12 illustrates a block diagram of a system including a base stationthat supports a reduced overhead EDC design for decoding a codeword inaccordance with aspects of the present disclosure.

FIGS. 13 through 17 illustrate methods for reduced overhead EDC designfor decoding a codeword in accordance with aspects of the presentdisclosure.

DETAILED DESCRIPTION

The described techniques relate to improved methods, systems, devices,or apparatuses that support techniques for reducing error detection codeoverhead. Generally, the described techniques reduce error detectionoverhead by generating code block level (CB-level) error detection codes(EDCs) for a subset of code blocks (CBs) in a transport block (TB) and aTB-level EDC for the TB, and generating a codeword using the CB-levelEDCs and the TB-level. The reduced EDC overhead may improve datathroughput and reduce decoding latency at a receiver, and improve thelikelihood of meeting transmission latency specifications (e.g., 0.5 msfor uplink and downlink transmissions), or block error ratio (which mayalso be referred to as block error rate) (BLER) specifications (e.g.,10⁻⁵ BLER, 10⁻⁹ BLER, etc.), or both, for certain types ofcommunications, such as ultra-reliable low latency communications(URLLC).

CRC overhead in a TB may be significant in conventional systems, whichmay reduce data throughput and increase transmission latency. Bygenerating a CB-level EDC for only a subset of the plurality of datasegments, a transmitting device as described herein may reduce CRCoverhead experienced by conventional systems. In an example, an encoderof a wireless device may receive a TB for transmission and segment theTB into a set of multiple, smaller data segments. The encoder maygenerate a CB-level EDC for a subset of the data segments, and theCB-level EDCs and the data segments may be included in respective CBsthat are each the same size (e.g., each CB includes the same number ofbits). The encoder may also generate a transport block-level (TB-level)EDC for the TB using the data segments.

A subset of the CBs may include a data segment from the subset of thedata segments and one of the CB-level EDCs. The remaining one or moreCBs that are not a part of the subset may include a remaining one of thedata segments and the TB-level EDC. EDC overhead may be reduced by atleast one CB-level EDC, as the one or more CBs that are not part of thesubset may not also include a CB-level EDC. The CB that includes theTB-level EDC may be the same length as the other CBs of the TB (e.g.,CBs with a data segment and a CB-level EDC). Thus, the same codes may beapplied for each CB of the TB.

Prior to communicating with the receiving device, the transmittingwireless device may signal to the receiving device a coding scheme beingused (e.g., a polar code being used to encode a TB), and which subset ofthe CBs in the TB include the CB-level EDC, and which one or more CBs inthe TB include the TB-level EDC. The transmitting wireless device maygenerate a codeword from the TB, the subset of the CB-level EDCs, andthe TB-level EDC. The transmitting wireless device may, for example,encode the TB, the subset of the CB-level EDC, and the TB-level EDCaccording to the polar code to generate the codeword, and modulate thecodeword for transmission to a receiving wireless device via a wirelesschannel.

The receiving wireless device may receive, via the wireless channel, asignal that includes the modulated codeword. The receiving device maydemodulate and decode the signal to obtain a candidate bit sequence,using, for example, a list decoding algorithm according to the samepolar code used to generate the codeword. The receiving device mayattempt to determine whether the candidate bit sequence passes errordetection. If the candidate bit sequence passes, the receiving devicemay obtain the TB from the candidate bit sequence and determine that thereceived TB is the same TB as sent by the transmitting device.

To perform error detection, the receiving device may parse the candidatebit sequence into bit subsequences having a same length as the length ofthe CBs, and perform CB-level error detection on the bit subsequences,which may include a data segment and a CB-level EDC, or a data segmentand a TB-level EDC. In some cases, the receiving device may identify afirst data segment of a first CB of the CBs using a CB-level errordetection code of the first CB. The receiving device may also identify asecond data segment of a second CB of the CBs using a CB-level detectioncode of the second CB. If each data segment in a subset of the CBspasses CB-level error detection, the receiving device may then check theTB-level EDC and corresponding data segment. In some cases, thereceiving device may generate a TB by combining the first data segmentand the second data segment, and perform a TB-level error detectiondetermination of the first data segment and the second data segment ofthe TB using a TB-level error detection code.

In some cases, the receiving device may determine that the first datasegment and the second data segment passed error detection based atleast in part on determining CB-level error detection determinationsassociated with the first CB and second CB and the TB-level errordetection determination do not indicate an error. In some cases, thereceiving device may set the TB-level error detection determination toindicate that an error was identified based on determining that at leastone of the CB-level error detection determinations associated with thefirst CB and the second CB indicates an error. In some cases, thereceiving device may determine that none of the CB-level error detectiondeterminations associated with the first CB and the second CB indicatean error, and the receiving device may perform an error detectionalgorithm on the first data segment and the second data segment togenerate the TB-level error detection determination.

In some cases, the receiving device may generate a calculated TB-levelEDC based at least in part of the first data segment and the second datasegment, obtain a received TB-level EDC from the second CB, and comparethe calculated TB-level EDC and the received TB-level EDC, where theTB-level detection determination indicates whether the calculatedTB-level EDC matches the received TB-level EDC. If error detection forthe TB-level EDC fails, but each CB-level EDC passes, the receivingdevice may request a retransmission for the data segment associated withthe TB-level EDC and none of the other data segments. The receivingdevice may then transmit feedback requesting a retransmission of theunsuccessfully received data segment.

If one or more of the CB-level EDCs fail, the receiving device mayrequest a retransmission of each data segment which failed errordetection as well as the data segment associated with the TB-level EDC.In some examples, the receiving device may perform an early terminationof decoding the TB-level EDC and corresponding data segment based on aCB-level EDC failing error detection. Beneficially, the techniquesdescribed herein may reduce error detection overhead and reduce decodingcomplexity, to improve the likelihood of a communication meeting BLERand/or transmission latency specifications.

Aspects of the disclosure are initially described in the context of awireless communications system. Aspects of the disclosure are furtherillustrated by and described with reference to apparatus diagrams,system diagrams, and flowcharts that relate to reduced overhead EDCdesign for decoding a codeword.

FIG. 1 illustrates an example of a wireless communications system 100 inaccordance with various aspects of the present disclosure. The wirelesscommunications system 100 includes base stations 105, UEs 115, and acore network 130. In some examples, the wireless communications system100 may be a Long Term Evolution (LTE) network, an LTE-Advanced (LTE-A)network, or a New Radio (NR) network. In some cases, wirelesscommunications system 100 may support enhanced broadband communications,ultra-reliable (e.g., mission critical) communications, low latencycommunications, or communications with low-cost and low-complexitydevices.

Base stations 105 may wirelessly communicate with UEs 115 via one ormore base station antennas. Base stations 105 described herein mayinclude or may be referred to by those skilled in the art as a basetransceiver station, a radio base station, an access point, a radiotransceiver, a NodeB, an eNodeB (eNB), a next-generation Node B orgiga-nodeB (either of which may be referred to as a gNB), a Home NodeB,a Home eNodeB, or some other suitable terminology. Wirelesscommunications system 100 may include base stations 105 of differenttypes (e.g., macro or small cell base stations). The UEs 115 describedherein may be able to communicate with various types of base stations105 and network equipment including macro eNBs, small cell eNBs, gNBs,relay base stations, and the like.

Each base station 105 may be associated with a particular geographiccoverage area 110 in which communications with various UEs 115 issupported. Each base station 105 may provide communication coverage fora respective geographic coverage area 110 via communication links 125,and communication links 125 between a base station 105 and a UE 115 mayutilize one or more carriers. Communication links 125 shown in wirelesscommunications system 100 may include uplink transmissions from a UE 115to a base station 105, or downlink transmissions, from a base station105 to a UE 115. Downlink transmissions may also be called forward linktransmissions while uplink transmissions may also be called reverse linktransmissions.

The geographic coverage area 110 for a base station 105 may be dividedinto sectors making up only a portion of the geographic coverage area110, and each sector may be associated with a cell. For example, eachbase station 105 may provide communication coverage for a macro cell, asmall cell, a hot spot, or other types of cells, or various combinationsthereof. In some examples, a base station 105 may be movable andtherefore provide communication coverage for a moving geographiccoverage area 110. In some examples, different geographic coverage areas110 associated with different technologies may overlap, and overlappinggeographic coverage areas 110 associated with different technologies maybe supported by the same base station 105 or by different base stations105. The wireless communications system 100 may include, for example, aheterogeneous LTE/LTE-A or NR network in which different types of basestations 105 provide coverage for various geographic coverage areas 110.

The term “cell” refers to a logical communication entity used forcommunication with a base station 105 (e.g., over a carrier), and may beassociated with an identifier for distinguishing neighboring cells(e.g., a physical cell identifier (PCID), a virtual cell identifier(VCID)) operating via the same or a different carrier. In some examples,a carrier may support multiple cells, and different cells may beconfigured according to different protocol types (e.g., machine-typecommunication (MTC), narrowband Internet-of-Things (NB-IoT), enhancedmobile broadband (eMBB), or others) that may provide access fordifferent types of devices. In some cases, the term “cell” may refer toa portion of a geographic coverage area 110 (e.g., a sector) over whichthe logical entity operates.

UEs 115 may be dispersed throughout the wireless communications system100, and each UE 115 may be stationary or mobile. A UE 115 may also bereferred to as a mobile device, a wireless device, a remote device, ahandheld device, or a subscriber device, or some other suitableterminology, where the “device” may also be referred to as a unit, astation, a terminal, or a client. A UE 115 may also be a personalelectronic device such as a cellular phone, a personal digital assistant(PDA), a tablet computer, a laptop computer, or a personal computer. Insome examples, a UE 115 may also refer to a wireless local loop (WLL)station, an Internet of Things (IoT) device, an Internet of Everything(IoE) device, or an MTC device, or the like, which may be implemented invarious articles such as appliances, vehicles, meters, or the like.

Some UEs 115, such as MTC or IoT devices, may be low cost or lowcomplexity devices, and may provide for automated communication betweenmachines (e.g., via Machine-to-Machine (M2M) communication). M2Mcommunication or MTC may refer to data communication technologies thatallow devices to communicate with one another or a base station 105without human intervention. In some examples, M2M communication or MTCmay include communications from devices that integrate sensors or metersto measure or capture information and relay that information to acentral server or application program that can make use of theinformation or present the information to humans interacting with theprogram or application. Some UEs 115 may be designed to collectinformation or enable automated behavior of machines. Examples ofapplications for MTC devices include smart metering, inventorymonitoring, water level monitoring, equipment monitoring, healthcaremonitoring, wildlife monitoring, weather and geological eventmonitoring, fleet management and tracking, remote security sensing,physical access control, and transaction-based business charging.

Some UEs 115 may be configured to employ operating modes that reducepower consumption, such as half-duplex communications (e.g., a mode thatsupports one-way communication via transmission or reception, but nottransmission and reception simultaneously). In some examples half-duplexcommunications may be performed at a reduced peak rate. Other powerconservation techniques for UEs 115 include entering a power saving“deep sleep” mode when not engaging in active communications, oroperating over a limited bandwidth (e.g., according to narrowbandcommunications). In some cases, UEs 115 may be designed to supportcritical functions (e.g., mission critical functions), and a wirelesscommunications system 100 may be configured to provide ultra-reliablecommunications for these functions.

In some cases, a UE 115 may also be able to communicate directly withother UEs 115 (e.g., using a peer-to-peer (P2P) or device-to-device(D2D) protocol). One or more of a group of UEs 115 utilizing D2Dcommunications may be within the geographic coverage area 110 of a basestation 105. Other UEs 115 in such a group may be outside the geographiccoverage area 110 of a base station 105, or be otherwise unable toreceive transmissions from a base station 105. In some cases, groups ofUEs 115 communicating via D2D communications may utilize a one-to-many(1:M) system in which each UE 115 transmits to every other UE 115 in thegroup. In some cases, a base station 105 facilitates the scheduling ofresources for D2D communications. In other cases, D2D communications arecarried out between UEs 115 without the involvement of a base station105.

Base stations 105 may communicate with the core network 130 and with oneanother. For example, base stations 105 may interface with the corenetwork 130 through backhaul links 132 (e.g., via an S1 or otherinterface). Base stations 105 may communicate with one another overbackhaul links 134 (e.g., via an X2 or other interface) either directly(e.g., directly between base stations 105) or indirectly (e.g., via corenetwork 130).

The core network 130 may provide user authentication, accessauthorization, tracking, Internet Protocol (IP) connectivity, and otheraccess, routing, or mobility functions. The core network 130 may be anevolved packet core (EPC), which may include at least one mobilitymanagement entity (MME), at least one serving gateway (S-GW), and atleast one Packet Data Network (PDN) gateway (P-GW). The MME may managenon-access stratum (e.g., control plane) functions such as mobility,authentication, and bearer management for UEs 115 served by basestations 105 associated with the EPC. User IP packets may be transferredthrough the S-GW, which itself may be connected to the P-GW. The P-GWmay provide IP address allocation as well as other functions. The P-GWmay be connected to the network operators IP services. The operators IPservices may include access to the Internet, Intranet(s), an IPMultimedia Subsystem (IMS), or a Packet-Switched (PS) Streaming Service.

At least some of the network devices, such as a base station 105, mayinclude subcomponents such as an access network entity, which may be anexample of an access node controller (ANC). Each access network entitymay communicate with UEs 115 through a number of other access networktransmission entities, which may be referred to as a radio head, a smartradio head, or a transmission/reception point (TRP). In someconfigurations, various functions of each access network entity or basestation 105 may be distributed across various network devices (e.g.,radio heads and access network controllers) or consolidated into asingle network device (e.g., a base station 105).

Wireless communications system 100 may operate using one or morefrequency bands, typically in the range of 300 megahertz (MHz) to 300gigahertz (GHz). Generally, the region from 300 MHz to 3 GHz is known asthe ultra-high frequency (UHF) region or decimeter band, since thewavelengths range from approximately one decimeter to one meter inlength. UHF waves may be blocked or redirected by buildings andenvironmental features. However, the waves may penetrate structuressufficiently for a macro cell to provide service to UEs 115 locatedindoors. Transmission of UHF waves may be associated with smallerantennas and shorter range (e.g., less than 100 km) compared totransmission using the smaller frequencies and longer waves of the highfrequency (HF) or very high frequency (VHF) portion of the spectrumbelow 300 MHz.

Wireless communications system 100 may also operate in a super highfrequency (SHF) region using frequency bands from 3 GHz to 30 GHz, alsoknown as the centimeter band. The SHF region includes bands such as the5 GHz industrial, scientific, and medical (ISM) bands, which may be usedopportunistically by devices that can tolerate interference from otherusers.

Wireless communications system 100 may also operate in an extremely highfrequency (EHF) region of the spectrum (e.g., from 25 GHz to 300 GHz),also known as the millimeter band. In some examples, wirelesscommunications system 100 may support millimeter wave (mmW)communications between UEs 115 and base stations 105, and EHF antennasof the respective devices may be even smaller and more closely spacedthan UHF antennas. In some cases, this may facilitate use of antennaarrays within a UE 115. However, the propagation of EHF transmissionsmay be subject to even greater atmospheric attenuation and shorter rangethan SHF or UHF transmissions. Techniques disclosed herein may beemployed across transmissions that use one or more different frequencyregions, and designated use of bands across these frequency regions maydiffer by country or regulating body.

In some cases, wireless communications system 100 may utilize bothlicensed and unlicensed radio frequency spectrum bands. For example,wireless communications system 100 may employ License Assisted Access(LAA), LTE-Unlicensed (LTE-U) radio access technology, or NR technologyin an unlicensed band such as the 5 GHz ISM band. When operating inunlicensed radio frequency spectrum bands, wireless devices such as basestations 105 and UEs 115 may employ listen-before-talk (LBT) proceduresto ensure a frequency channel is clear before transmitting data. In somecases, operations in unlicensed bands may be based on a CA configurationin conjunction with CCs operating in a licensed band (e.g., LAA).Operations in unlicensed spectrum may include downlink transmissions,uplink transmissions, peer-to-peer transmissions, or a combination ofthese. Duplexing in unlicensed spectrum may be based on frequencydivision duplexing (FDD), time division duplexing (TDD), or acombination of both.

In some examples, base station 105 or UE 115 may be equipped withmultiple antennas, which may be used to employ techniques such astransmit diversity, receive diversity, multiple-input multiple-output(MIMO) communications, or beamforming. For example, wirelesscommunications system 100 may use a transmission scheme between atransmitting device (e.g., a base station 105) and a receiving device(e.g., a UE 115), where the transmitting device is equipped withmultiple antennas and the receiving devices are equipped with one ormore antennas. MIMO communications may employ multipath signalpropagation to increase the spectral efficiency by transmitting orreceiving multiple signals via different spatial layers, which may bereferred to as spatial multiplexing. The multiple signals may, forexample, be transmitted by the transmitting device via differentantennas or different combinations of antennas. Likewise, the multiplesignals may be received by the receiving device via different antennasor different combinations of antennas. Each of the multiple signals maybe referred to as a separate spatial stream, and may carry bitsassociated with the same data stream (e.g., the same codeword) ordifferent data streams. Different spatial layers may be associated withdifferent antenna ports used for channel measurement and reporting. MIMOtechniques include single-user MIMO (SU-MIMO) where multiple spatiallayers are transmitted to the same receiving device, and multiple-userMIMO (MU-MIMO) where multiple spatial layers are transmitted to multipledevices.

Beamforming, which may also be referred to as spatial filtering,directional transmission, or directional reception, is a signalprocessing technique that may be used at a transmitting device or areceiving device (e.g., a base station 105 or a UE 115) to shape orsteer an antenna beam (e.g., a transmit beam or receive beam) along aspatial path between the transmitting device and the receiving device.Beamforming may be achieved by combining the signals communicated viaantenna elements of an antenna array such that signals propagating atparticular orientations with respect to an antenna array experienceconstructive interference while others experience destructiveinterference. The adjustment of signals communicated via the antennaelements may include a transmitting device or a receiving deviceapplying certain amplitude and phase offsets to signals carried via eachof the antenna elements associated with the device. The adjustmentsassociated with each of the antenna elements may be defined by abeamforming weight set associated with a particular orientation (e.g.,with respect to the antenna array of the transmitting device orreceiving device, or with respect to some other orientation).

In one example, a base station 105 may use multiple antennas or antennaarrays to conduct beamforming operations for directional communicationswith a UE 115. For instance, some signals (e.g., synchronizationsignals, reference signals, beam selection signals, or other controlsignals) may be transmitted by a base station 105 multiple times indifferent directions, which may include a signal being transmittedaccording to different beamforming weight sets associated with differentdirections of transmission. Transmissions in different beam directionsmay be used to identify (e.g., by the base station 105 or a receivingdevice, such as a UE 115) a beam direction for subsequent transmissionand/or reception by the base station 105. Some signals, such as datasignals associated with a particular receiving device, may betransmitted by a base station 105 in a single beam direction (e.g., adirection associated with the receiving device, such as a UE 115). Insome examples, the beam direction associated with transmissions along asingle beam direction may be determined based at least in in part on asignal that was transmitted in different beam directions. For example, aUE 115 may receive one or more of the signals transmitted by the basestation 105 in different directions, and the UE 115 may report to thebase station 105 an indication of the signal it received with a highestsignal quality, or an otherwise acceptable signal quality. Althoughthese techniques are described with reference to signals transmitted inone or more directions by a base station 105, a UE 115 may employsimilar techniques for transmitting signals multiple times in differentdirections (e.g., for identifying a beam direction for subsequenttransmission or reception by the UE 115), or transmitting a signal in asingle direction (e.g., for transmitting data to a receiving device).

A receiving device (e.g., a UE 115, which may be an example of a mmWreceiving device) may try multiple receive beams when receiving varioussignals from the base station 105, such as synchronization signals,reference signals, beam selection signals, or other control signals. Forexample, a receiving device may try multiple receive directions byreceiving via different antenna subarrays, by processing receivedsignals according to different antenna subarrays, by receiving accordingto different receive beamforming weight sets applied to signals receivedat a plurality of antenna elements of an antenna array, or by processingreceived signals according to different receive beamforming weight setsapplied to signals received at a plurality of antenna elements of anantenna array, any of which may be referred to as “listening” accordingto different receive beams or receive directions. In some examples areceiving device may use a single receive beam to receive along a singlebeam direction (e.g., when receiving a data signal). The single receivebeam may be aligned in a beam direction determined based at least inpart on listening according to different receive beam directions (e.g.,a beam direction determined to have a highest signal strength, highestsignal-to-noise ratio, or otherwise acceptable signal quality based atleast in part on listening according to multiple beam directions).

In some cases, the antennas of a base station 105 or UE 115 may belocated within one or more antenna arrays, which may support MIMOoperations, or transmit or receive beamforming. For example, one or morebase station antennas or antenna arrays may be co-located at an antennaassembly, such as an antenna tower. In some cases, antennas or antennaarrays associated with a base station 105 may be located in diversegeographic locations. A base station 105 may have an antenna array witha number of rows and columns of antenna ports that the base station 105may use to support beamforming of communications with a UE 115.Likewise, a UE 115 may have one or more antenna arrays that may supportvarious MIMO or beamforming operations.

In some cases, wireless communications system 100 may be a packet-basednetwork that operate according to a layered protocol stack. In the userplane, communications at the bearer or Packet Data Convergence Protocol(PDCP) layer may be IP-based. A Radio Link Control (RLC) layer may insome cases perform packet segmentation and reassembly to communicateover logical channels. A Medium Access Control (MAC) layer may performpriority handling and multiplexing of logical channels into transportchannels. The MAC layer may also use hybrid automatic repeat request(HARQ) to provide retransmission at the MAC layer to improve linkefficiency. In the control plane, the Radio Resource Control (RRC)protocol layer may provide establishment, configuration, and maintenanceof an RRC connection between a UE 115 and a base station 105 or corenetwork 130 supporting radio bearers for user plane data. At thePhysical (PHY) layer, transport channels may be mapped to physicalchannels.

In some cases, UEs 115 and base stations 105 may support retransmissionsof data to increase the likelihood that data is received successfully.HARQ feedback is one technique of increasing the likelihood that data isreceived correctly over a communication link 125. HARQ may include acombination of error detection (e.g., using a cyclic redundancy check(CRC)), forward error correction (FEC), and retransmission (e.g.,automatic repeat request (ARQ)). HARQ may improve throughput at the MAClayer in poor radio conditions (e.g., signal-to-noise conditions). Insome cases, a wireless device may support same-slot HARQ feedback, wherethe device may provide HARQ feedback in a specific slot for datareceived in a previous symbol in the slot. In other cases, the devicemay provide HARQ feedback in a subsequent slot, or according to someother time interval.

Time intervals in LTE or NR may be expressed in multiples of a basictime unit, which may, for example, refer to a sampling period ofT_(s)=1/30,720,000 seconds. Time intervals of a communications resourcemay be organized according to radio frames each having a duration of 10milliseconds (ms), where the frame period may be expressed as Tf=307,200T_(s). The radio frames may be identified by a system frame number (SFN)ranging from 0 to 1023. Each frame may include 10 subframes numberedfrom 0 to 9, and each subframe may have a duration of 1 ms. A subframemay be further divided into 2 slots each having a duration of 0.5 ms,and each slot may contain 6 or 7 modulation symbol periods (e.g.,depending on the length of the cyclic prefix prepended to each symbolperiod). Excluding the cyclic prefix, each symbol period may contain2048 sampling periods. In some cases, a subframe may be the smallestscheduling unit of the wireless communications system 100, and may bereferred to as a transmission time interval (TTI). In other cases, asmallest scheduling unit of the wireless communications system 100 maybe shorter than a subframe or may be dynamically selected (e.g., inbursts of shortened TTIs (sTTIs) or in selected component carriers usingsTTIs).

In some wireless communications systems, a slot may further be dividedinto multiple mini-slots containing one or more symbols. In someinstances, a symbol of a mini-slot or a mini-slot may be the smallestunit of scheduling. Each symbol may vary in duration depending on thesubcarrier spacing or frequency band of operation, for example. Further,some wireless communications systems may implement slot aggregation inwhich multiple slots or mini-slots are aggregated together and used forcommunication between a UE 115 and a base station 105.

The term “carrier” refers to a set of radio frequency spectrum resourceshaving a defined physical layer structure for supporting communicationsover a communication link 125. For example, a carrier of a communicationlink 125 may include a portion of a radio frequency spectrum band thatis operated according to physical layer channels for a given radioaccess technology. Each physical layer channel may carry user data,control information, or other signaling. A carrier may be associatedwith a pre-defined frequency channel (e.g., an E-UTRA absolute radiofrequency channel number (EARFCN)), and may be positioned according to achannel raster for discovery by UEs 115. Carriers may be downlink oruplink (e.g., in an FDD mode), or be configured to carry downlink anduplink communications (e.g., in a TDD mode). In some examples, signalwaveforms transmitted over a carrier may be made up of multiplesub-carriers (e.g., using multi-carrier modulation (MCM) techniques suchas orthogonal frequency-division multiplexing (OFDM) or DFT-s-OFDM).

The organizational structure of the carriers may be different fordifferent radio access technologies (e.g., LTE, LTE-A, NR, etc.). Forexample, communications over a carrier may be organized according toTTIs or slots, each of which may include user data as well as controlinformation or signaling to support decoding the user data. A carriermay also include dedicated acquisition signaling (e.g., synchronizationsignals or system information, etc.) and control signaling thatcoordinates operation for the carrier. In some examples (e.g., in acarrier aggregation configuration), a carrier may also have acquisitionsignaling or control signaling that coordinates operations for othercarriers.

Physical channels may be multiplexed on a carrier according to varioustechniques. A physical control channel and a physical data channel maybe multiplexed on a downlink carrier, for example, using time divisionmultiplexing (TDM) techniques, frequency division multiplexing (FDM)techniques, or hybrid TDM-FDM techniques. In some examples, controlinformation transmitted in a physical control channel may be distributedbetween different control regions in a cascaded manner (e.g., between acommon control region or common search space and one or more UE-specificcontrol regions or UE-specific search spaces).

A carrier may be associated with a particular bandwidth of the radiofrequency spectrum, and in some examples the carrier bandwidth may bereferred to as a “system bandwidth” of the carrier or the wirelesscommunications system 100. For example, the carrier bandwidth may be oneof a number of predetermined bandwidths for carriers of a particularradio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 MHz). Insome examples, each served UE 115 may be configured for operating overportions or all of the carrier bandwidth. In other examples, some UEs115 may be configured for operation using a narrowband protocol typethat is associated with a predefined portion or range (e.g., set ofsubcarriers or RBs) within a carrier (e.g., “in-band” deployment of anarrowband protocol type).

In a system employing MCM techniques, a resource element may include onesymbol period (e.g., a duration of one modulation symbol) and onesubcarrier, where the symbol period and subcarrier spacing are inverselyrelated. The number of bits carried by each resource element may dependon the modulation scheme (e.g., the order of the modulation scheme).Thus, the more resource elements that a UE 115 receives and the higherthe order of the modulation scheme, the higher the data rate may be forthe UE 115. In MIMO systems, a wireless communications resource mayrefer to a combination of a radio frequency spectrum resource, a timeresource, and a spatial resource (e.g., spatial layers), and the use ofmultiple spatial layers may further increase the data rate forcommunications with a UE 115.

Devices of the wireless communications system 100 (e.g., base stations105 or UEs 115) may have a hardware configuration that supportscommunications over a particular carrier bandwidth, or may beconfigurable to support communications over one of a set of carrierbandwidths. In some examples, the wireless communications system 100 mayinclude base stations 105 and/or UEs 115 that can support simultaneouscommunications via carriers associated with more than one differentcarrier bandwidth.

Wireless communications system 100 may support communication with a UE115 on multiple cells or carriers, a feature which may be referred to ascarrier aggregation (CA) or multi-carrier operation. A UE 115 may beconfigured with multiple downlink CCs and one or more uplink CCsaccording to a carrier aggregation configuration. Carrier aggregationmay be used with both FDD and TDD component carriers.

In some cases, wireless communications system 100 may utilize enhancedcomponent carriers (eCCs). An eCC may be characterized by one or morefeatures including wider carrier or frequency channel bandwidth, shortersymbol duration, shorter TTI duration, or modified control channelconfiguration. In some cases, an eCC may be associated with a carrieraggregation configuration or a dual connectivity configuration (e.g.,when multiple serving cells have a suboptimal or non-ideal backhaullink). An eCC may also be configured for use in unlicensed spectrum orshared spectrum (e.g., where more than one operator is allowed to usethe spectrum). An eCC characterized by wide carrier bandwidth mayinclude one or more segments that may be utilized by UEs 115 that arenot capable of monitoring the whole carrier bandwidth or are otherwiseconfigured to use a limited carrier bandwidth (e.g., to conserve power).

In some cases, an eCC may utilize a different symbol duration than otherCCs, which may include use of a reduced symbol duration as compared withsymbol durations of the other CCs. A shorter symbol duration may beassociated with increased spacing between adjacent subcarriers. Adevice, such as a UE 115 or base station 105, utilizing eCCs maytransmit wideband signals (e.g., according to frequency channel orcarrier bandwidths of 20, 40, 60, 80 MHz, etc.) at reduced symboldurations (e.g., 16.67 microseconds). A TTI in eCC may include one ormultiple symbol periods. In some cases, the TTI duration (that is, thenumber of symbol periods in a TTI) may be variable.

Wireless communications systems such as an NR system may utilize anycombination of licensed, shared, and unlicensed spectrum bands, amongothers. The flexibility of eCC symbol duration and subcarrier spacingmay allow for the use of eCC across multiple spectrums. In someexamples, NR shared spectrum may increase spectrum utilization andspectral efficiency, specifically through dynamic vertical (e.g., acrossfrequency) and horizontal (e.g., across time) sharing of resources.

An encoder of a transmitting wireless device, such as a base station 105or a UE 115, may segment a TB into multiple, smaller data segments. Theencoder may generate a CB-level EDC for some of the data segments. Theencoder may generate a TB-level EDC for the TB, and the TB-level EDC maybe included in a CB with at least one of the data segments. EDC overheadmay be reduced by at least one CB-level EDC, as the data segment withthe TB-level EDC may not also include a CB-level EDC.

The transmitting wireless device may generate a codeword from the CBsand modulate the codeword for transmission to a receiving device. Thereceiving wireless device may demodulate and decode the signal to obtaina candidate bit sequence. The receiving wireless device may determine,on a CB by CB basis, whether each data segment has been successfullyreceived based on a CB-level EDC included in a corresponding CB. In somecases, the receiving wireless device may identify a first data segmentof a first CB of the CBs using a CB-level error detection code of thefirst CB. The receiving wireless device may also identify a second datasegment of a second CB of the CBs using a CB-level detection code of thesecond CB. If each data segment passes error detection, the receivingwireless device may check the TB-level EDC. In some cases, the receivingwireless device may generate a TB by combining the first data segmentand the second data segment, and perform a TB-level error detectiondetermination of the first data segment and the second data segment ofthe TB using a TB-level error detection code.

In some cases, the receiving wireless device may determine that thefirst data segment and the second data segment passed error detectionbased on determining CB-level error detection determinations associatedwith the first CB and second CB and the TB-level error detectiondetermination do not indicate an error. In some cases, the receivingwireless device may set the TB-level error detection determination toindicate that an error was identified based on determining that at leastone of CB-level error detection determinations associated with the firstCB and the second CB indicates an error. In some cases, the receivingdevice may determine that none of CB-level error detectiondeterminations associated with the first CB and the second CB indicatean error, and perform an error detection algorithm on the first datasegment and the second data segment to generate the TB-level errordetection determination. In some cases, the receiving device maygenerate a calculated TB-level EDC based at least in part of the firstdata segment and the second data segment, obtain a received TB-level EDCfrom the second CB, and compare the calculated TB-level EDC and thereceived TB-level EDC, where the TB-level detection determinationindicates whether the calculated TB-level EDC matches the receivedTB-level EDC. The receiving wireless device may request retransmissionfor one or more of the data segments that did not pass error detection,up to all data segments of a TB. In some cases, the receiving wirelessdevice may perform an early termination of decoding the TB-level EDC andcorresponding data segment based on a CB-level EDC failing errordetection.

FIG. 2 illustrates an example of a wireless communications system 200that supports a reduced overhead error detection code design fordecoding a codeword in accordance with various aspects of the presentdisclosure. In some examples, wireless communications system 200 mayimplement aspects of wireless communications system 100. Wirelesscommunications system 200 may include base station 105-a, which may bean example of a base station 105 as described with reference to FIG. 1.

Base station 105-a may encode a TB that includes a set of informationbits for transmission to a UE 115-a (see FIG. 3) via a wirelesscommunication channel. In other examples, a UE 115-a may encode a TB fortransmission to base station 105-a or another UE using these sametechniques. In further examples, base station 105-a may encode a TB fortransmission to another base station 105-a using these same techniques.Moreover, devices other than base station 105-a and UE 115-a may use thetechniques described herein.

In the depicted example, base station 105-a may include a data source205, a segmentor 215, an EDC generator 225, a codeword generator 235,and a modulator 245. The data source 205 may provide a TB 210 thatincludes a set of s information bits to be encoded and transmitted tothe UE 115-a. The data source 205 may be coupled to a network, a storagedevice, or the like. The data source 205 may output the TB 210 to theEDC generator 225. The segmentor 215 may segment the TB 210 intomultiple data segments that each include the same number of bits, or atleast one of the data segments may have a different number of bits thanthe other data segments. Segmentation may be an efficient way to meetlatency and/or BLER specifications imposed by the wirelesscommunications system 200. In some examples, polar codes may have betterperformance for payload sizes of less than a defined number of bits(e.g., 300 bits) compared with low-density parity-check (LDPC) codes andTurbo codes. Further, decoding latency may be decreased by reducing atotal number of information bits and parity bits in a CB (e.g., byreducing a mother code size (e.g., CB size having a power of two)) bysegmenting the TB 210 into smaller data segments that are respectivelyincluded in CBs of the TB 210. The segmentor 215 may pass the pluralityof data segments 220 to the EDC generator 225.

EDC generator 225 may apply an error detecting algorithm to datasegments 220 of the TB for generation of CB-level and TB-level EDCs. AnEDC may be a code to enable the receiving device to detect an error in areceived TB due to, for example, corruption from noise in a wirelesschannel. In an example, the EDC algorithm may be a CRC algorithm, andthe EDC may be a CRC.

The EDC generator 225 may apply the error detecting algorithm to asubset of the data segments 220 to generate a CB-level EDC for each datasegment in the subset of data segments 220. For example, the TB 210 mayinclude N data segments corresponding to N CBs, where Nis a positiveinteger. The subset of data segments 220 may include up to N−1 of the Ndata segments. EDC generator 225 may generate a CB-level EDC for each CBbased on the corresponding data segment in the subset of the datasegments. For example, a first CB may include a first data segment, andthe EDC generator 225 may apply an error detecting algorithm to thefirst data segment to generate a CB-level EDC for the first CB. The EDCgenerator 225 may similarly generate a CB-level EDC for the remainingCBs in the subset of the CBs. The EDC generator 225 may also apply anerror detection algorithm as a function of up to all of the datasegments of the TB 210 to generate a TB-level EDC for the TB 210.

The EDC generator 225 may form each CB by appending an EDC to one of thedata segments of the TB. A subset of the CBs may each include one of thedata segments and a CB-level EDC. At least one of the CBs may include adata segment and a TB-level EDC. For example, the EDC generator 225 maygenerate a subset of CBs that each include a CB-level EDC for each datasegment, and a last CB may include a data segment and the TB-level EDC.

In some examples, base station 105-a may generate CBs 230 as depicted bythe EDC design 400 in FIG. 4. For example, the TB 210 may be segmentedinto data segment 410-a and data segment 410-b. The EDC generator 225may generate a CB-level EDC for each of the data segments. The EDCgenerator 225 may generate CB 420-a by appending data segment 410-a withCRC 425-a, which may be a CB-level EDC. The EDC generator 225 maygenerate CB 420-b by appending data segment 410-b with CRC 415 and CRC425-b, which may be respective examples of a TB-level EDC and a CB-levelEDC. However, by including both a TB-level EDC and a CB-level EDC in CB420-b, the EDC design 400 may have significant CRC overhead.

In another, more efficient example, the EDC generator 225 may generateCBs 230 as depicted by the efficient EDC design 500 in FIG. 5. Forexample, a TB may be split into two data segments, data segment 510-aand data segment 510-b. The EDC generator may generate a TB-level EDC,CRC 515, and a CB-level EDC, CRC 525. The EDC generator 225 may generateCB 520-a by appending CB-level CRC 525 to data segment 510-a. The EDCgenerator 225 may generate CB 520-b by appending TB-level CRC 515 todata segment 510-b. In some examples CB 520-a and CB 520-b may be thesame length or include the same number of bits. In comparison with CB420-b of FIG. 4, CB 520-b may not include a CB-level CRC 525, therebyreducing the CRC overhead when transmitting the TB.

In another embodiment, the EDC generator 225 may generate CBs 230 asdepicted by efficient EDC design 600 in FIG. 6. The efficient EDC design600 may be similar to the efficient EDC design 500, but the efficientEDC design 600 may be generalized for any number (e.g., N) of CBs 230.For example, the TB 210 may be split into N data segments, includingdata segment 610-a, data segment 610-b, and other data segments throughdata segment 610-n. The EDC generator 225 may generate a TB-level EDC,CRC 615, and N−1 CB-level EDCs, CRCs 625. The EDC generator 225 mayselect a subset of data segments 610 and append a CB-level EDC to eachdata segment 610 in the subset to generate CB 620-a through CB620-(n−1). The EDC generator 225 may select at data segment 610 notincluded in the subset and append CRC 615 (e.g., the TB-level EDC) togenerate CB 620-n. CB 620-n may not include a CB-level CRC 625, therebyreducing the CRC overhead when transmitting the TB. In some examples,each CB 620, including CB 620-n, may be the same length, or include thesame number of bits.

With reference again to FIG. 2, the EDC generator 225 may output the CBs230 to the codeword generator 235. The codeword generator 235 mayperform an encoding technique on the CBs 230 to generate a codeword 240.In some cases, the codeword 240 may be a polar-encoded codeword. Forexample, when encoding a TB, the codeword generator 235 may receive asinputs the plurality of CBs that each include one of the data segments.A subset of the CBs may include a CB-level EDC, and a remaining one ormore of the CBs may include the TB-level EDC. The codeword generator 235may encode the plurality of CBs according to a polar code to generatethe codeword 240. Other encoding techniques, such as LDPC and Turbocoding may also be used to generate codeword 240. The modulator 245 maymodulate the codeword 240 for transmission to a receiver via a wirelesscommunication channel, which may distort the signal 250 carrying thecodeword 240 with noise.

FIG. 3 illustrates an example of a wireless communications system 300that supports a reduced overhead EDC design for decoding a codeword inaccordance with various aspects of the present disclosure. In someexamples, wireless communications system 300 may implement aspects ofwireless communications system 100. Wireless communications system 300may include UE 115-a, which may be an example of a UE 115 as describedwith reference to FIGS. 1-2.

UE 115-a may receive a signal 305 that includes codeword. For example,the codeword may be an example of codeword 240 transmitted by the basestation 105-a of FIG. 2. In an example, UE 115-a may include ademodulator 310, a decoder 320, and an EDC checker 330. The demodulator310 may receive the signal 305 including the codeword and input thedemodulated signal 315 into decoder 320 for decoding of the codeword.The demodulated signal may be, for example, a sequence oflogarithmic-likelihood ratio (LLR) values representing a probabilityvalue of a received bit being a ‘0’ or a ‘1’. The decoder 320 mayperform a list decoding algorithm on the LLR values and output acandidate bit sequence 325. UE 115-a may send the candidate bit sequence325 to an EDC checker 330. The EDC checker 330 may determine whether thecandidate bit sequence 325 passes error detection, or whether to requestretransmission of some portions of the candidate bit sequence 325. Ifthe candidate bit sequence 325 passes error detection, the UE 115-adetermines that it has properly received the TB sent by the base station105-a.

The EDC checker 330 may determine whether the candidate bit sequence 325passed error detection based on the CB-level and TB-level EDCs includedin the codeword 240 transmitted by the base station 105-a. Based onprior signaling with the base station 105-a, or based on apre-configuration, UE 115-a may be aware of the TB size (e.g., number ofbits in the TB), a location and order of the CBs of the TB, a CB size(e.g., number of bits in the CB), an EDC size (e.g., number of bitsrespectively in the CB-level and TB-level EDCs), the location ofCB-level EDCs within a CB, the subset of the CBs that include theCB-level EDCs, and which one or more CBs includes the TB-level EDC.Based on the signaling or the pre-configuration, the EDC checker 330 mayobtain bit subsequences from the candidate bit sequence 325corresponding to each CB of the TB. In some cases, the obtained bitsubsequences may each include the same number of bits and may be thesame size of the CBs.

In some cases, the candidate bit sequence 325 may correspond to anefficient EDC design 500 as illustrated in FIG. 5. For example, the TBmay be split into two data segments, data segment 510-a and data segment510-b. The EDC checker 330 may calculate a CB-level EDC based on thebits in the candidate bit sequence 325 corresponding to the data segment510-a. If the calculated CB-level EDC matches the CB-level EDC includedin bit subsequence obtained from the candidate bit sequence 325, the EDCchecker 330 may determine that data segment 510-a passes errordetection. In some cases, the EDC checker 330 may identify a first datasegment of a first CB of the CBs using a CB-level error detection codeof the first CB. The EDC checker 330 may also identify a second datasegment of a second CB of the CBs using a CB-level detection code of thesecond CB. The EDC checker 330 may similarly determine whether the otherCBs in the subset pass CB-level error detection.

If all CBs in the subset pass CB-level error detection, the EDC checker330 may then calculate a TB-level EDC for the TB (e.g., including datasegment 510-a and data segment 510-b). The EDC checker 330 may obtainthe bit subsequence from the candidate bit sequence 325 for theidentified CB 520-b that includes the TB-level CRC. The EDC checker 330may obtain a data segment 510-b from the identified CB 520-b, and thedata segments corresponding to the subset of CBs that passed errordetection, and perform the error detection algorithm using all of thedata segments to calculate a TB-level EDC. If the calculated TB-levelEDC matches the TB-level EDC 515 obtained from the identified CB 520-bincluded in the candidate bit sequence 325, the EDC checker 330 maydetermine that data segment 510-b, and TB 505, both pass errordetection. In some cases, the EDC checker 330 may determine that thefirst data segment and the second data segment passed error detectionbased on determining CB-level error detection determinations associatedwith the first CB and second CB and the TB-level error detectiondetermination do not indicate an error. In some cases, the EDC checker330 may set the TB-level error detection determination to indicate thatan error was identified based on determining that at least one ofCB-level error detection determinations associated with the first CB andthe second CB indicates an error. In some cases, the EDC checker 330 maydetermine that none of CB-level error detection determinationsassociated with the first CB and the second CB indicate an error, andperform an error detection algorithm on the first data segment and thesecond data segment to generate the TB-level error detectiondetermination. In some cases, the EDC checker 330 may generate acalculated TB-level error detection code (EDC) based at least in part ofthe first data segment and the second data segment, obtain a receivedTB-level EDC from the second CB, and compare the calculated TB-level EDCand the received TB-level EDC, where the TB-level detectiondetermination indicates whether the calculated TB-level EDC matches thereceived TB-level EDC. In some cases, the EDC checker 330 may havereduced EDC overhead based on CB 520-b not having an appended CB-levelCRC 525.

In another example, the candidate bit sequence 325 may correspond to anefficient EDC design 600 as illustrated in FIG. 6. The efficient EDCdesign 600 may be similar to the efficient EDC design 500, but theefficient EDC design 600 may be generalized for any number (e.g., N) ofCBs 230. For example, the TB 210 may be split into N data segments,including data segment 610-a, data segment 610-b, and other datasegments 610 through data segment 610-n. The EDC checker 330 maycalculate CB-level EDCs for each segment of bits in the candidate bitsequence 325 corresponding to a data segment 610 which was encoded by aCB-level EDC (e.g., each data segment except for data segment 610-n). Ifthe calculated CB-level EDC matches the CB-level EDC in the candidatebit sequence, the corresponding data segment may pass CB-level errordetection, and this process may repeat for each of the subset of CBs.

If all CBs in the subset pass CB-level error detection, the EDC checker330 may then calculate a TB-level EDC for the TB 605. Similar to thedescription provided above, the EDC checker 330 may calculate a TB-levelEDC using the data segments of the TB 605 obtained from the candidatebit sequence 325. The EDC checker 330 may obtain the bit subsequencefrom the candidate bit sequence 325 for the identified CB 620-n thatincludes the TB-level CRC 615. The EDC checker 330 may obtain a datasegment 610-n from the identified CB 620-n, and the data segments 610-ato 610-(n−1) corresponding to the subset of CBs that passed errordetection, and perform the error detection algorithm using all of thedata segments to calculate a TB-level EDC. If the calculated TB-levelEDC matches the TB-level EDC 615 obtained from the identified CB 620-nincluded in the candidate bit sequence 325, the EDC checker 330 maydetermine that data segment 610-n, and TB 605, both pass errordetection. In some cases, the EDC checker 330 may have improved errordetection rates based on CB 620-n not having an appended CB-level CRC625, which reduces the CRC overhead for the TB. In some examples, eachCB 620, including CB 620-n, may be the same length, or include the samenumber of bits.

For the subset of CBs that include a CB-level EDC, the EDC checker 330may make a CB-level error detection determination for each CB in thesubset of the CBs. For example, EDC checker 330 may determine that afirst bit subsequence includes corresponds to bits of a first CB in thesubset of CBs that each include a CB-level EDC. Based on the known sizesof the data segment and the CB-level EDC, the EDC checker 330 may obtainfrom the first bit subsequence the data segment and a received CB-levelEDC. The EDC checker 330 may generate a calculated CB-level EDC byapplying to the data segment obtained from the bit subsequence the sameEDC algorithm that the base station 105-a applied to the data segment ofthe first CB. The EDC checker 330 may compare the received CB-level EDCto the calculated CB-level EDC, and determine that the first CB passederror detection if the received CB-level EDC matches the calculatedCB-level EDC.

If the calculated EDC and the received EDC match, EDC checker 330 maydetermine that the data segment received in the first CB passed errordetection, and the EDC checker 330 may output the data segment forfurther processing by the UE 115-a. Otherwise, the EDC checker 330 maydetermine that the first CB did not pass error detection. The EDCchecker 330 may similarly perform error detection on the bitsubsequences corresponding to the other CBs in the subset of CBs thateach include a CB-level EDC. In some examples, EDC checker 330 mayperform error detection on multiple CBs and corresponding CB-level EDCsin parallel, simultaneously, or substantially simultaneously.

Performing error detection at the CB-level EDC may also enable earlytermination of the decoding process or assist path pruning in anEDC-aided successive cancellation list (e.g., CRC-aided successivecancellation list (CA-SCL)) applied by the decoder 320 when decoding acodeword (e.g., a polar encoded codeword). For example, the EDC checker330 may obtain one or more bit subsequences of at least one candidatebit sequence 325 from the decoder 320 prior to the decoder 320generating all bits of the candidate bit sequence 325. In list decoding,the decoder 320 may generate multiple paths through a code tree and mayextend each path on a bit by bit basis based on the LLR values. Eachpath through the code tree may correspond to a different candidate bitsequence 325. The EDC checker 330 may determine that a bit subsequencecorresponding to a first CB in a particular candidate bit sequence 325does not pass error detection, and the decoder 320 optionally may prunea path corresponding to that particular candidate bit sequence 325. Ifall paths are pruned in such a manner, the decoder 320 may terminate thedecoding process early.

If one or more of the CBs in the subset of CBs do not pass CB-levelerror detection, the EDC checker 330 may, in some examples, skipchecking the TB-level EDC, which may improve decoding rates or feedbacktiming. For example, the EDC checker 330 may set a TB-level errordetection determination to indicate that an error was identified basedat least in part on determining that at least one of the CB-level errordetection determinations indicates an error.

If all of the CBs in the subset of CBs pass CB-level error detection,the EDC checker 330 may make a TB-level error detection determination.In an example, the EDC checker 330 may identify a bit subsequence in thecandidate bit sequence 325 that corresponds to bits of an identified CBof the CBs that includes the TB-level EDC and an identified datasegment. The EDC checker 330 may form a candidate TB from the datasegments that each passed the CB-level EDC check and the identified datasegment. Similar to the discussion of the CB-level EDC check, the EDCchecker 330 may generate a calculated TB-level EDC by applying to thedata segments of the candidate TB the same EDC algorithm that the basestation 105-a applied to the data segments of the first TB. The EDCchecker 330 may compare the received TB-level EDC to the calculatedTB-level EDC, and determine that the first TB passed error detection ifthe received TB-level EDC matches the calculated TB-level EDC.Otherwise, the EDC checker 330 may determine that the candidate TB didnot pass error detection.

The EDC checker 330 may generate an error detection determinationassociated with the plurality of data segments based at least in part onthe CB-level error detection determinations and the TB-level errordetection determination. If all CBs and TBs passed error detection, theEDC checker 330 may determine that TB, including the plurality of datasegments, passed error detection and output the TB for furtherprocessing by the UE 115.

If at least one CB does not pass error detection, or the TB-level EDCdid not pass error detection, UE 115-a may request a retransmission ofthe corresponding CB(s) or the entire TB. For a TB that includes N CBs,UE 115-a may transmit an N-bit sequence to the transmitting device(e.g., base station 105-a of FIG. 2) which indicates which zero or moreCBs of the TB did not pass error detection, and which zero or more CBsof the TB passed error. For example, a ‘0’ may indicate a CB passederror detection, and a ‘1’ may indicate the CB did not pass errordetection. In some examples, base station 105-a may receive a sequenceof bits, which may indicate a request for a retransmission of one ormore data segments. Base station 105-a may generate a second codeword asdescribed with reference to FIG. 2 and retransmit the requested datasegments in the second codeword. Base station 105-a may include newinformation bits in the second codeword in addition to the retransmitteddata segment(s).

While the example of FIG. 2 describes the base station 105-a performingthe encoding and FIG. 3 describes UE 115-a performing the decoding, theroles may be reversed. Moreover, devices other than the base station105-a and the UE 115-a may perform the encoding and decoding.

FIG. 4 illustrates an example of an EDC design 400 that supports areduced overhead EDC design for decoding a codeword in accordance withvarious aspects of the present disclosure. In some examples, EDC design400 may implement aspects of wireless communications system 100.

A transmitting device may segment a TB 405 into data segment 410-a(e.g., S₁) and data segment 410-b (e.g., S₂). In some cases, CRC may beattached to each data segment 410 to improve decoding performance.Separate CRC bits may be applied for the TB 405 and the CBs 420. Forexample, TB-level CRC 415 may encode data segment 410-a and data segment410-b at the TB level. CRC 425-a may encode data segment 410-a at a CBlevel, and CRC 425-b may encode data segment 410-b and TB-level CRC_(TB)415 at a CB level. In some examples, a CRC (e.g., TB-level CRC 415 or aCRC 425) may be 24 bits long. In some examples, CRC 415 may check TB 405(e.g., data segment 410-a+data segment 410-b) after data segment 410-aand data segment 410-b are checked by CRC 425-a and CRC 425-brespectively.

In some cases, the overall CRC overhead in FIG. 4 may become large whenthe data segments 410 are not large. For example, the CRC overhead asillustrated may be large when there are two CBs 420 and three CRCs(e.g., CRCs 425-a and 425-b and TB-level CRC 415) applied for the twoCBs 420. In some instances, EDC design 400 may not be efficient forURLLC with medium-sized or small TBs.

By instead implementing an EDC design as described with reference toFIG. 5 or 6, CRC overhead may be significantly reduced (e.g., for Polarcodes with middle-sized CBs). For example, if TB 405 may include 400bits, and the transmitting device may use a 24-bit design for CRCs 425and CRC 415. Therefore, EDC design 400 may have a CRC overhead of 18%(24 bits per CRC*3 CRCs/400 bits per TB). However, a base station 105-aimplementing the techniques illustrated in FIG. 5 for the same TB mayhave a CRC overhead of 12% (24 bits per CRC*2 CRCs/400 bits per TB).Therefore, EDC design 400 may be inefficient compared to the efficientEDC design 500 or 600, resulting in less throughput, longerencoding/decoding times, or significantly larger EDC overhead. In anexample, a 400-bits TB, that is segmented into two CBs, may have a codedblock size of 512 bits. In some examples, the EDC designs 500 and 600may reduce decoding complex since the CRC check at CB level is omittedfor the last CB 520-b and CBN 620-n. In some examples, the algorithmdescribed herein, for a list size of 8 in a CA-SCL decoder, may achievea coding gain relative to conventional solutions regardless of thenumber of information bits included in the TB.

FIG. 5 illustrates an example of an efficient EDC design 500 thatsupports a reduced overhead EDC design for decoding a codeword inaccordance with various aspects of the present disclosure. In someexamples, efficient EDC design 500 may implement aspects of wirelesscommunications system 100. The efficient EDC design 500 may beimplemented by a UE 115 or a base station 105 as described herein withreference to FIGS. 1 through 3.

TB 505 may similarly include two data segments 510, data segment 510-aand data segment 510-b. TB-level CRC 515 may encode the data segments510 at a TB level. CRC 525 may be used to encode data segment 510-a at aCB level, generating CB 520. Instead of generating a CRC 525 for each CB520, the TB-level CRC 515 may be used as a CB-level CRC, and TB-levelCRC 515 may be appended to data segment 510-b to generate CB 520-b.TB-level CRC may be generated based on both data segments 510. In someexamples, the length of CB 520-a may be equal to the length of CB 520-b.That is, the length of data segment 510-a and CRC 525 may be equal tothe length of data segment 510-b and TB-level CRC 515. By having CBs 520of similar length, the same codes may be applied to CB 520-a and CB520-b, and the same decoder may be used for CB 520-a and 520-b. In someexamples, TB-level CRC 515 may be longer than CRC 525. In some cases,the extra length of TB-level CRC 515 may provide lower undetectableerror probability.

For a receiving device, TB-level CRC 515 may be used to check TB 505after data segment 510-a is checked by CRC 515. In some examples,checking data segment 510-a first may be used for path pruning in CA-SCLdecoding for Polar codes. Thus, by checking data segment 510-a first,the receiving device may perform early termination of the TB 505, as thereceiving device may not check data segment 510-b if data segment 510-afails. In some cases, the receiving device may identify data segment510-a of CB 520-a using a CB-level error detection code of the first CB.The receiving device may also identify data segment 510-b of CB 520-busing a CB-level detection code of the second CB. In some cases, thereceiving device may generate TB 505 by combining the decoded datasegment 510-a and the decoded data segment 510-b, and perform a TB-levelerror detection determination of the decoded data segment 510-a and thedecoded data segment 510-b of TB 505 using a TB-level error detectioncode.

In some cases, the receiving device may determine that data segment510-a and data segment 510-b passed error detection based at least inpart on determining CB-level error detection determinations associatedwith CB 520-a and CB 520-b and the TB-level error detectiondetermination do not indicate an error. In some cases, the receivingdevice may set the TB-level error detection determination to indicatethat an error was identified based on determining that at least one ofCB-level error detection determinations associated with CB 520-a and CB520-b indicates an error. In some cases, the receiving device maydetermine that none of CB-level error detection determinationsassociated with CB 520-a and CB 520-b indicate an error, and perform anerror detection algorithm on data segment 510-a and data segment 510-bto generate the TB-level error detection determination. In some cases,the receiving device may generate a calculated TB-level EDC based atleast in part of the decoded data segment 510-a and the decoded datasegment 510-b, obtain a received TB-level EDC from CB 520-b, and comparethe calculated TB-level EDC and the received TB-level EDC, where theTB-level detection determination indicates whether the calculatedTB-level EDC matches the received TB-level EDC.

The receiving device may request retransmission of one or more datasegments 510 based on whether the data segments 510 were successfully orunsuccessfully received. For example, if CRC 525 passes error detectionbut CRC 515 fails, the receiving device may determine that data segment510-a was received successfully, and data segment 510-b was not.Therefore, the receiving device may request a retransmission of datasegment 510-b. In another example, CRC 525 may fail, and the receivingdevice may early terminate the decoding procedure and request aretransmission of both data segments 525.

FIG. 6 illustrates an example of an efficient EDC design 600 thatsupports a reduced overhead EDC design for decoding a codeword inaccordance with various aspects of the present disclosure. In someexamples, efficient EDC design 600 may implement aspects of wirelesscommunications system 100. The efficient EDC design 600 may beimplemented by a UE 115 or a base station 105 as described herein withreference to FIGS. 1 through 3.

Efficient EDC design 600 may be similar to the efficient EDC design 500,but the efficient EDC design 600 may be generalized to N CBs 620. Thatis, the TB 605 may be segmented into N data segments 610. TB-level CRC615 may be generated based on each data segment 610, or all informationbits, in the TB 605. As described above, CRC 625-a may encode datasegment 610-a, CRC 625-b may encode data segment 610-b, etc. In someexamples, the length of each CB may be the same to ensure that the samecodes are applied for each CB and the same decoder may be used for eachCB. For example, the length of data segment S_(i)+CRC_(i), where i=1, 2. . . , n, may be equal to the length of S_(N)+CRC_(TB). In someexamples, the length of TB-level CRC 615 may be larger than that of aCRC 625 to provide lower undetectable error probability. In someexamples, the number of bits in data segment 610-a may be fewer than theother data segments 610-a to 610-(n−1) to account for TB-level CRC 615having more bits than the CB-level CRC 625.

As described herein, a receiving device may use TB-level CRC 615 tocheck TB 605 after each data segment 610, except for data segment 610-n,is checked by the corresponding CRC 625. In some examples, checking thedata segment 610 encoded by a CB-level CRC 625 first may be used forpath pruning in CRC-aided successive cancellation list (CA-SCL) decodingfor polar codes. Thus, by checking the data segments 610 encoded by aCRC 625 first, the receiving device may perform early termination of theTB 605, as the receiving device may skip checking a TB-level CRC if aprevious data segment 610 fails.

The receiving device may request retransmission of data segments 610based on whether the data segments 610 were successfully received. Forexample, if each CRC 625 passes, but TB-level CRC 615 fails, thereceiving device may determine that data segment 610-n was notsuccessfully received, while each other data segment 610 wassuccessfully received. Therefore, the receiving device may request aretransmission of data segment 510-b. In another example, CRC 625-b mayfail, but each other CRC 625 may pass. The receiving device may earlyterminate the decoding procedure of data segment 610-n and request aretransmission of data segment 610-b and data segment 610-n. In general,the receiving device may request retransmission of any data segment 610which has a failed CB-level error detection. If any of the CRCs 625fail, the receiving device may early terminate a decoding procedure ofthe TB-level CRC 615 and request a retransmission of data segment 610-n.

For example, the receiving device may transmit an n-bit HARQ sequence tothe transmitting device, where each bit corresponds to a data segment610. If a bit in the HARQ sequence is a ‘1’, this may indicate a requestfor a retransmission of the corresponding data segment 610. If a bit inthe HARQ sequence is a ‘0’, this may indicate that the correspondingdata segment 610 was successfully received.

FIG. 7 illustrates an example of a process flow 700 that supports areduced overhead EDC design for decoding a codeword in accordance withvarious aspects of the present disclosure. In some examples, processflow 700 may implement aspects of wireless communications system 100.Process flow 700 may illustrate UE 115-b and base station 105-b, whichmay be respective examples of a UE 115 and base station 105 as describedherein. While process flow 700 illustrates base station 105-b generatinga codeword according to an efficient EDC design and UE 115-b decodingthe codeword according to the efficient EDC design, in some examples UE115-b may generate the codeword and base station 105-b may decode thecodeword, among other various configurations.

At 705, base station 105-b may segment a TB into a plurality of datasegments. At 710, base station 105-b may generate a CB-level EDC foreach data segment of a subset of the plurality of data segments. In someexamples, base station 105-b may generate the CB-level EDC for each ofthe data segments in the set other than an identified data segment ofthe plurality of data segments.

At 715, base station 105-b may generate a TB-level EDC based on theplurality of data segments. In some cases, base station 105-b mayassociate each data segment of the plurality of data segments with arespective CB of a plurality of CBs, where an identified CB of theplurality of CBs includes the identified data segment and the TB-levelEDC. In some cases, each of the plurality of CBs other than theidentified CB may include a respective data segment of the plurality ofdata segments other than the identified data segment and a respectiveCB-level EDC of the CB-level EDCs. In some cases, the CB-level EDCs mayinclude a first number of bits, and the TB-level EDCs may include asecond number of bits which is different from the first number of bits.In some examples, each of the CBs may be of the same size (e.g., includethe same number of bits).

At 720, base station 105-b may generate a codeword. The codeword may begenerated based on the plurality of data segments, the CB-level EDCs forthe subset of the plurality of data segments, and the TB-level EDC. Thebase station 105-b may encode the plurality of data segments, theCB-level EDCs for the subset of the plurality of data segments, and theTB-level EDC according to a polar code to generate a polar-encodedcodeword. Then, at 725, base station 105-b may transmit the codeword toUE 115-b. In some examples, base station 105-b may indicate to the UE115-b a coding scheme being used to generate the codeword, which subsetof the CBs in the TB include the CB-level EDC, and which one or more CBsin the TB include the TB-level EDC.

UE 115-b may receive a signal including the codeword and process thesignal to obtain a candidate bit sequence. In some cases, UE 115-b mayperform a list decoding algorithm to decode the codeword according to apolar code to generate the candidate bit sequence. At 730, UE 115-b maysegment the candidate bit sequence into a plurality of CBs that eachinclude a respective data segment of a plurality of data segments.

At 735, UE 115-b may generate a CB-level error detection determinationfor each CB of a subset of the plurality of CBs. In some cases, theCB-level error detection determination includes generating a calculatedCB-level EDC for the first data segment, obtaining a received CB-levelEDC from the first CB, and comparing the calculated CB-level EDC and thereceived CB-level and determining whether the calculated CB-level EDCmatches the received CB-level EDC.

At 740, UE 115-b may generate a TB-level error detection determinationassociated with the plurality of data segments. In some cases, UE 115-bmay determine that none of the CB-level error detection determinationsindicate an error and perform an error detection algorithm on theplurality of data segments to generate the TB-level error detectiondetermination.

UE 115-b may then generate an error detection determination at 745. Theerror detection determination may be associated with the plurality ofdata segments based on the CB-level error detection determinations andthe TB-level error detection determinations. For example, the UE 115-bmay determine that the plurality of data segments passed error detectionbased on determining that each CB-level error detection determinationand the TB-level error detection determination do not indicate an error.

In some cases, UE 115-b may transmit feedback for the data segments at750. For example, UE 115-b may indicate to base station 105-b that thedata segments passed error detection. In another example, UE 115-b maytransmit feedback indicating that one or more of the plurality of datasegments did not pass error detection based on the CB-level errordetection determinations. In some cases, UE 115-b may transmit feedbackindicating that the error detection algorithm detected a TB-level error.

At 755, base station 105-b, in some cases, may generate a secondcodeword based on the feedback and one or more indicated data segmentswhich did not pass error detection. In some examples, the secondcodeword may be generated as described herein, and base station 105-bmay transmit new information with the retransmitted data segments. Thebase station 105-b may transmit the second codeword to UE 115-b at 760.

FIG. 8 shows a block diagram 800 of a wireless device 805 that supportsa reduced overhead EDC design for decoding a codeword in accordance withaspects of the present disclosure. Wireless device 805 may be an exampleof aspects of a user equipment (UE) 115 or base station 105 as describedherein. Wireless device 805 may include receiver 810, communicationsmanager 815, and transmitter 820. Wireless device 805 may also include aprocessor. Each of these components may be in communication with oneanother (e.g., via one or more buses).

Receiver 810 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to reducedoverhead EDC design for decoding a codeword, etc.). Information may bepassed on to other components of the wireless device 805. The receiver810 may be an example of aspects of the transceiver 1135 described withreference to FIG. 11. The receiver 810 may utilize a single antenna or aset of antennas.

Communications manager 815 may be an example of aspects of thecommunications manager 1115 described with reference to FIG. 11.Communications manager 815 and/or at least some of its varioussub-components may be implemented in hardware, software executed by aprocessor, firmware, or any combination thereof. If implemented insoftware executed by a processor, the functions of the communicationsmanager 815 and/or at least some of its various sub-components may beexecuted by a general-purpose processor, a digital signal processor(DSP), an application-specific integrated circuit (ASIC), afield-programmable gate array (FPGA) or other programmable logic device,discrete gate or transistor logic, discrete hardware components, or anycombination thereof designed to perform the functions described in thepresent disclosure. The communications manager 815 and/or at least someof its various sub-components may be physically located at variouspositions, including being distributed such that portions of functionsare implemented at different physical locations by one or more physicaldevices. In some examples, communications manager 815 and/or at leastsome of its various sub-components may be a separate and distinctcomponent in accordance with various aspects of the present disclosure.In other examples, communications manager 815 and/or at least some ofits various sub-components may be combined with one or more otherhardware components, including but not limited to an I/O component, atransceiver, a network server, another computing device, one or moreother components described in the present disclosure, or a combinationthereof in accordance with various aspects of the present disclosure.

Communications manager 815 may segment a TB into a plurality of datasegments, generate a CB-level EDC for each data segment of a subset ofthe plurality of data segments, generate a TB-level EDC based on theplurality of data segments, generate a codeword based on the pluralityof data segments, the CB-level EDCs for the subset of the plurality ofdata segments, and the TB-level EDC, and transmit the codeword via awireless channel. The communications manager 815 may also process asignal including a codeword to obtain a candidate bit sequence, segmentthe candidate bit sequence into a plurality of CBs that each include arespective data segment of a plurality of data segments, generate aCB-level error detection determination for each CB of a subset of theplurality of CBs, generate a TB-level error detection determinationassociated with the plurality of data segments, and generate an errordetection determination associated with the plurality of data segmentsbased on the CB-level error detection determinations and the TB-levelerror detection determination. In some cases, communications manager 815may process signal comprising a codeword to obtain a candidate bitsequence, segment the candidate bit sequence into a plurality of CBsthat each comprises a respective data segment of a plurality of datasegments, identify a first data segment of a first CB of the pluralityof CBs using a CB-level EDC of the first CB, identify a second datasegment of a second CB of the plurality of CBs using a CB-leveldetection code of the second CB, generate a TB by combining the firstdata segment and the second data segment, and perform a TB-level errordetection determination of the first data segment and the second datasegment of the TB using a TB-level error detection code.

Transmitter 820 may transmit signals generated by other components ofthe wireless device 805. In some examples, the transmitter 820 may becollocated with a receiver 810 in a transceiver module. For example, thetransmitter 820 may be an example of aspects of the transceiver 1135described with reference to FIG. 11. The transmitter 820 may utilize asingle antenna or a set of antennas.

FIG. 9 shows a block diagram 900 of a wireless device 905 that supportsa reduced overhead error detection code design for decoding a codewordin accordance with aspects of the present disclosure. Wireless device905 may be an example of aspects of a wireless device 805 or a UE 115 orbase station 105 as described with reference to FIG. 8. Wireless device905 may include receiver 910, communications manager 915, andtransmitter 920. Wireless device 905 may also include a processor. Eachof these components may be in communication with one another (e.g., viaone or more buses).

Receiver 910 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to reducedoverhead error detection code design for decoding a codeword, etc.).Information may be passed on to other components of the wireless device905. The receiver 910 may be an example of aspects of the transceiver1135 described with reference to FIG. 11. The receiver 910 may utilize asingle antenna or a set of antennas.

Communications manager 915 may be an example of aspects of thecommunications manager 1115 described with reference to FIG. 11.Communications manager 915 may also include segmentor 925, CB-level EDCgenerator 930, TB-level EDC generator 935, codeword generator 940,codeword communicator 945, candidate bit sequence identifier 950,candidate bit sequence segmentor 955, CB-level error detector 960,TB-level error detector 965, and data segment error detector 970.Segmentor 925 may segment a TB into a plurality of data segments.

CB-level EDC generator 930 may generate a CB level CB-level EDC for eachdata segment of a subset of the plurality of data segments. In somecases, generating the CB-level EDC for each data segment of the subsetof the plurality of data segments includes: generating the CB-level EDCfor each of the plurality of data segments other than an identified datasegment of the plurality of data segments.

TB-level EDC generator 935 may generate a TB-level EDC based on theplurality of data segments. In some cases, each of the CB-level EDCsincludes a first number of bits and the TB-level EDC includes a secondnumber of bits that differs from the first number of bits. In somecases, at least one CB of a plurality of CBs includes the TB-level EDCand a data segment of the plurality of data segments that has fewer bitsthan at least one other data segment of the plurality of data segments.In some cases, each of the CB-level EDCs is a CB-level CRC and theTB-level EDC is a TB-level CRC.

Codeword generator 940 may generate a codeword based on the plurality ofdata segments, the CB-level EDCs for the subset of the plurality of datasegments, and the TB-level EDC. In some cases, generating the codewordincludes: encoding the plurality of data segments, the CB-level EDCs,and the TB-level EDC using a polar code to obtain the codeword. Codewordcommunicator 945 may transmit the codeword via a wireless channel.

Candidate bit sequence identifier 950 may process a signal including acodeword to obtain a candidate bit sequence. In some cases, processingthe signal including the codeword to obtain the candidate bit sequenceincludes: performing a list decoding algorithm to decode the codewordaccording to a polar code to generate the candidate bit sequence.

Candidate bit sequence segmentor 955 may segment the candidate bitsequence into a plurality of CBs that each include a respective datasegment of a plurality of data segments.

CB-level error detector 960 may generate a CB-level error detectiondetermination for each CB of a subset of the plurality of CBs, generatea calculated CB-level EDC for the first data segment, obtain a receivedCB-level EDC from the first CB, and compare the calculated CB-level EDCand the received CB-level EDC, where the CB-level error detectiondetermination for the first CB indicates whether the calculated CB-levelEDC matches the received CB-level EDC. In some cases, generating theCB-level error detection determination for each CB of the subset of theplurality of CBs includes: obtaining a first data segment of theplurality of data segments from a first CB of the plurality of CBs. Insome cases, CB-level error detector 1055 may identify a first datasegment of a first CB of the plurality of CBs using a CB-level errordetection code of the first CB. In some cases, CB-level error detector1055 may also identify a second data segment of a second CB of theplurality of CBs using a CB-level error detection code of the second CB.

TB-level error detector 965 may generate a TB-level error detectiondetermination associated with the plurality of data segments, perform anerror detection algorithm on the plurality of data segments to generatethe TB-level error detection determination, transmit feedback indicatingthat the plurality of data segments passed error detection, obtain areceived TB-level EDC from an identified CB of the plurality of CBs, andcompare the calculated TB-level EDC and the received TB-level EDC, wherethe TB-level error detection determination indicates whether thecalculated TB-level EDC matches the received TB-level EDC. In somecases, generating the TB-level error detection determination includes:setting the TB-level error detection determination to indicate that anerror was identified based on determining that at least one of theCB-level error detection determinations indicate an error. In somecases, generating the TB-level error detection determination includes:determining that none of the CB-level error detection determinationsindicate an error. In some cases, performing the error detectionalgorithm includes: transmitting feedback indicating that the errordetection algorithm detected a TB-level error. In some cases, performingthe error detection algorithm includes: determining that the errordetection algorithm did not detect a TB-level error. In some cases,generating the TB-level error detection determination includes:generating a calculated TB-level EDC based on the plurality of datasegments.

In some cases, TB-level error detector 965 may perform a TB-level errordetection determination of a first data segment and a second datasegment of a TB using a TB-level error detection code. In some cases,TB-level error detector 965 may determine that the first data segmentand the second data segment passed error detection based at least inpart on determining CB-level error detection determinations associatedwith the first CB and second CB and the TB-level error detectiondetermination do not indicate an error. In some cases, TB-level errordetector 965 may set the TB-level error detection determination toindicate that an error was identified based at least in part ondetermining that at least one of CB-level error detection determinationsassociated with the first CB and the second CB indicates an error. Insome cases, TB-level error detector 965 may determine that none ofCB-level error detection determinations associated with the first CB andthe second CB indicate an error, and perform an error detectionalgorithm on the first data segment and the second data segment togenerate the TB-level error detection determination. In some cases,TB-level error detector 965 may generate a calculated TB-level errordetection code (EDC) based at least in part of the first data segmentand the second data segment, obtain a received TB-level EDC from thesecond CB, and compare the calculated TB-level EDC and the receivedTB-level EDC, where the TB-level detection determination indicateswhether the calculated TB-level EDC matches the received TB-level EDC.

Data segment error detector 970 may generate an error detectiondetermination associated with the plurality of data segments based onthe CB-level error detection determinations and the TB-level errordetection determination. In some cases, generating the error detectiondetermination associated with the plurality of data segments includes:determining that the plurality of data segments passed error detectionbased on determining that each of the CB-level error detectiondeterminations and the TB-level error detection determination do notindicate an error.

Transmitter 920 may transmit signals generated by other components ofthe wireless device 905. In some examples, the transmitter 920 may becollocated with a receiver 910 in a transceiver module. For example, thetransmitter 920 may be an example of aspects of the transceiver 1135described with reference to FIG. 11. The transmitter 920 may utilize asingle antenna or a set of antennas.

FIG. 10 shows a block diagram 1000 of a communications manager 1015 thatsupports a reduced overhead EDC design for decoding a codeword inaccordance with aspects of the present disclosure. The communicationsmanager 1015 may be an example of aspects of a communications manager815, a communications manager 915, or a communications manager 1115described with reference to FIGS. 8, 9, and 11. The communicationsmanager 1015 may include segmentor 1020, CB-level EDC generator 1025,TB-level EDC generator 1030, codeword generator 1035, codewordcommunicator 1040, candidate bit sequence identifier 1045, candidate bitsequence segmentor 1050, CB-level error detector 1055, TB-level errordetector 1060, data segment error detector 1065, CB component 1070,feedback responder 1075, and feedback requester 1080. Each of thesemodules may communicate, directly or indirectly, with one another (e.g.,via one or more buses).

Segmentor 1020 may segment a TB into a plurality of data segments.CB-level EDC generator 1025 may generate a CB-level EDC for each datasegment of a subset of the plurality of data segments. In some cases,generating the CB-level EDC for each data segment of the subset of theplurality of data segments includes: generating the CB-level EDC foreach of the plurality of data segments other than an identified datasegment of the plurality of data segments.

TB-level EDC generator 1030 may generate a TB-level EDC based on theplurality of data segments. In some cases, each of the CB-level EDCsincludes a first number of bits and the TB-level EDC includes a secondnumber of bits that differs from the first number of bits. In somecases, at least one CB of a plurality of CBs includes the TB-level EDCand a data segment of the plurality of data segments that has fewer bitsthan at least one other data segment of the plurality of data segments.In some cases, each of the CB-level EDCs is a CB-level CRC and theTB-level EDC is a TB-level CRC.

Codeword generator 1035 may generate a codeword based on the pluralityof data segments, the CB-level EDCs for the subset of the plurality ofdata segments, and the TB-level EDC. In some cases, generating thecodeword includes: encoding the plurality of data segments, the CB-levelEDCs, and the TB-level EDC using a polar code to obtain the codeword.Codeword communicator 1040 may transmit the codeword via a wirelesschannel.

Candidate bit sequence identifier 1045 may process a signal including acodeword to obtain a candidate bit sequence. In some cases, processingthe signal including the codeword to obtain the candidate bit sequenceincludes: performing a list decoding algorithm to decode the codewordaccording to a polar code to generate the candidate bit sequence.

Candidate bit sequence segmentor 1050 may segment the candidate bitsequence into a plurality of CBs that each include a respective datasegment of a plurality of data segments.

CB-level error detector 1055 may generate a CB-level error detectiondetermination for each CB of a subset of the plurality of CBs, generatea calculated CB-level EDC for the first data segment, obtain a receivedCB-level EDC from the first CB, and compare the calculated CB-level EDCand the received CB-level EDC, where the CB-level error detectiondetermination for the first CB indicates whether the calculated CB-levelEDC matches the received CB-level EDC. In some cases, generating theCB-level error detection determination for each CB of the subset of theplurality of CBs includes: obtaining a first data segment of theplurality of data segments from a first CB of the plurality of CBs. Insome cases, CB-level error detector 1055 may identify a first datasegment of a first CB of the plurality of CBs using a CB-level errordetection code of the first CB. In some cases, CB-level error detector1055 may also identify a second data segment of a second CB of theplurality of CBs using a CB-level error detection code of the second CB.

TB-level error detector 1060 may generate a TB-level error detectiondetermination associated with the plurality of data segments, perform anerror detection algorithm on the plurality of data segments to generatethe TB-level error detection determination, transmit feedback indicatingthat the plurality of data segments passed error detection, obtain areceived TB-level EDC from an identified CB of the plurality of CBs, andcompare the calculated TB-level EDC and the received TB-level EDC, wherethe TB-level error detection determination indicates whether thecalculated TB-level EDC matches the received TB-level EDC. In somecases, generating the TB-level error detection determination includes:setting the TB-level error detection determination to indicate that anerror was identified based on determining that at least one of theCB-level error detection determinations indicate an error. In somecases, generating the TB-level error detection determination includes:determining that none of the CB-level error detection determinationsindicate an error. In some cases, performing the error detectionalgorithm includes: transmitting feedback indicating that the errordetection algorithm detected a TB-level error. In some cases, performingthe error detection algorithm includes: determining that the errordetection algorithm did not detect a TB-level error. In some cases,generating the TB-level error detection determination includes:generating a calculated TB-level EDC based on the plurality of datasegments.

In some cases, TB-level error detector 1060 may perform a TB-level errordetection determination of a first data segment and a second datasegment of a TB using a TB-level error detection code. In some cases,TB-level error detector 1060 may determine that the first data segmentand the second data segment passed error detection based at least inpart on determining CB-level error detection determinations associatedwith the first CB and second CB and the TB-level error detectiondetermination do not indicate an error. In some cases, TB-level errordetector 1060 may set the TB-level error detection determination toindicate that an error was identified based at least in part ondetermining that at least one of CB-level error detection determinationsassociated with the first CB and the second CB indicates an error. Insome cases, TB-level error detector 1060 may determine that none ofCB-level error detection determinations associated with the first CB andthe second CB indicate an error, and perform an error detectionalgorithm on the first data segment and the second data segment togenerate the TB-level error detection determination. In some cases,TB-level error detector 1060 may generate a calculated TB-level errordetection code (EDC) based at least in part of the first data segmentand the second data segment, obtain a received TB-level EDC from thesecond CB, and compare the calculated TB-level EDC and the receivedTB-level EDC, where the TB-level detection determination indicateswhether the calculated TB-level EDC matches the received TB-level EDC.

Data segment error detector 1065 may generate an error detectiondetermination associated with the plurality of data segments based onthe CB-level error detection determinations and the TB-level errordetection determination. In some cases, generating the error detectiondetermination associated with the plurality of data segments includes:determining that the plurality of data segments passed error detectionbased on determining that each of the CB-level error detectiondeterminations and the TB-level error detection determination do notindicate an error.

CB component 1070 may associate each data segment of the plurality ofdata segments with a respective CB of a plurality of CBs, where anidentified CB of the plurality of CBs includes the identified datasegment and the TB-level EDC. In some cases, each of the plurality ofCBs other than the identified CB includes a respective data segment ofthe plurality of data segments other than the identified data segmentand a respective CB-level EDC of the CB-level EDCs.

Feedback responder 1075 may receive feedback indicating that at leastone data segment of the plurality of data segments did not pass errordetection, generate a second codeword based on the at least one datasegment, transmit the second codeword via the wireless channel, andprocess a sequence of bits included in the feedback to determine whichone or more of the plurality of data segments passed error detection andwhich one or more of the plurality of data segments did not pass errordetection.

Feedback requester 1080 may transmit feedback indicating that one ormore of the plurality of data segments did not pass error detectionbased on the CB-level error detection determinations. In some cases,feedback requester 1080 may transmit feedback indicating that an errordetection algorithm detected a TB-level error. In cases where the errordetection algorithm did not detect a TB-level error, feedback requester1080 may transmit feedback indicating that a first data segment and asecond data segment of the plurality of the data segments passed errordetection.

FIG. 11 shows a diagram of a system 1100 including a device 1105 thatsupports a reduced overhead error detection code design for decoding acodeword in accordance with aspects of the present disclosure. Device1105 may be an example of or include the components of wireless device805, wireless device 905, or a UE 115 as described herein, e.g., withreference to FIGS. 8 and 9. Device 1105 may include components forbi-directional voice and data communications including components fortransmitting and receiving communications, including UE communicationsmanager 1115, processor 1120, memory 1125, software 1130, transceiver1135, antenna 1140, and I/O controller 1145. These components may be inelectronic communication via one or more buses (e.g., bus 1110). Device1105 may communicate wirelessly with one or more base stations 105.

Processor 1120 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a central processing unit (CPU), amicrocontroller, an ASIC, an FPGA, a programmable logic device, adiscrete gate or transistor logic component, a discrete hardwarecomponent, or any combination thereof). In some cases, processor 1120may be configured to operate a memory array using a memory controller.In other cases, a memory controller may be integrated into processor1120. Processor 1120 may be configured to execute computer-readableinstructions stored in a memory to perform various functions (e.g.,functions or tasks supporting reduced overhead error detection codedesign for decoding a codeword).

Memory 1125 may include random-access memory (RAM) and read-only memory(ROM). The memory 1125 may store computer-readable, computer-executablesoftware 1130 including instructions that, when executed, cause theprocessor to perform various functions described herein. In some cases,the memory 1125 may contain, among other things, a basic input/outputsystem (BIOS) which may control basic hardware or software operationsuch as the interaction with peripheral components or devices.

Software 1130 may include code to implement aspects of the presentdisclosure, including code to support reduced overhead error detectioncode design for decoding a codeword. Software 1130 may be stored in anon-transitory computer-readable medium such as system memory or othermemory. In some cases, the software 1130 may not be directly executableby the processor but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

Transceiver 1135 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described herein. For example, thetransceiver 1135 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1135 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the device 1105 may include a single antenna 1140.However, in some cases the device 1105 may have more than one antenna1140, which may be capable of concurrently transmitting or receivingmultiple wireless transmissions.

I/O controller 1145 may manage input and output signals for device 1105.I/O controller 1145 may also manage peripherals not integrated intodevice 1105. In some cases, I/O controller 1145 may represent a physicalconnection or port to an external peripheral. In some cases, I/Ocontroller 1145 may utilize an operating system such as iOS®, ANDROID®,MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, or another known operatingsystem. In other cases, I/O controller 1145 may represent or interactwith a modem, a keyboard, a mouse, a touchscreen, or a similar device.In some cases, I/O controller 1145 may be implemented as part of aprocessor. In some cases, a user may interact with device 1105 via I/Ocontroller 1145 or via hardware components controlled by I/O controller1145.

FIG. 12 shows a diagram of a system 1200 including a device 1205 thatsupports a reduced overhead error detection code design for decoding acodeword in accordance with aspects of the present disclosure. Device1205 may be an example of or include the components of wireless device905, wireless device 1005, or a base station 105 as described herein,e.g., with reference to FIGS. 9 and 10. Device 1205 may includecomponents for bi-directional voice and data communications includingcomponents for transmitting and receiving communications, including basestation communications manager 1215, processor 1220, memory 1225,software 1230, transceiver 1235, antenna 1240, network communicationsmanager 1245, and inter-station communications manager 1250. Thesecomponents may be in electronic communication via one or more buses(e.g., bus 1210). Device 1205 may communicate wirelessly with one ormore UEs 115.

Processor 1220 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, anFPGA, a programmable logic device, a discrete gate or transistor logiccomponent, a discrete hardware component, or any combination thereof).In some cases, processor 1220 may be configured to operate a memoryarray using a memory controller. In other cases, a memory controller maybe integrated into processor 1220. Processor 1220 may be configured toexecute computer-readable instructions stored in a memory to performvarious functions (e.g., functions or tasks supporting reduced overheaderror detection code design for decoding a codeword).

Memory 1225 may include RAM and ROM. The memory 1225 may storecomputer-readable, computer-executable software 1230 includinginstructions that, when executed, cause the processor to perform variousfunctions described herein. In some cases, the memory 1225 may contain,among other things, a BIOS which may control basic hardware or softwareoperation such as the interaction with peripheral components or devices.

Software 1230 may include code to implement aspects of the presentdisclosure, including code to support reduced overhead error detectioncode design for decoding a codeword. Software 1230 may be stored in anon-transitory computer-readable medium such as system memory or othermemory. In some cases, the software 1230 may not be directly executableby the processor but may cause a computer (e.g., when compiled andexecuted) to perform functions described herein.

Transceiver 1235 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described herein. For example, thetransceiver 1235 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1235 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the device 1205 may include a single antenna 1240.However, in some cases the device 1205 may have more than one antenna1240, which may be capable of concurrently transmitting or receivingmultiple wireless transmissions.

Network communications manager 1245 may manage communications with thecore network (e.g., via one or more wired backhaul links). For example,the network communications manager 1245 may manage the transfer of datacommunications for client devices, such as one or more UEs 115.

Inter-station communications manager 1250 may manage communications withother base station 105, and may include a controller or scheduler forcontrolling communications with UEs 115 in cooperation with other basestations 105. For example, the inter-station communications manager 1250may coordinate scheduling for transmissions to UEs 115 for variousinterference mitigation techniques such as beamforming or jointtransmission. In some examples, inter-station communications manager1250 may provide an X2 interface within an LTE/LTE-A wirelesscommunication network technology to provide communication between basestations 105.

FIG. 13 shows a flowchart illustrating a method 1300 for reducedoverhead error detection code design for decoding a codeword inaccordance with aspects of the present disclosure. The operations ofmethod 1300 may be implemented by a UE 115 or base station 105 or itscomponents as described herein. For example, the operations of method1300 may be performed by a communications manager 815, 915, and 1015 asdescribed with reference to FIGS. 8 through 10. In some examples, a UE115 or base station 105 may execute a set of codes to control thefunctional elements of the device to perform the functions describedherein. Additionally or alternatively, the UE 115 or base station 105may perform aspects of the functions described herein usingspecial-purpose hardware.

At 1305, the UE 115 or base station 105 may segment a TB into aplurality of data segments. The operations of 1305 may be performedaccording to the methods described herein. In certain examples, aspectsof the operations of 1305 may be performed by a segmentor as describedwith reference to FIGS. 8 through 10.

At 1310, the UE 115 or base station 105 may generate a CB-level EDC foreach data segment of a subset of the plurality of data segments. Theoperations of 1310 may be performed according to the methods describedherein. In certain examples, aspects of the operations of 1310 may beperformed by a CB-level EDC generator as described with reference toFIGS. 8 through 10.

At 1315, the UE 115 or base station 105 may generate a TB-level EDCbased at least in part on the plurality of data segments. The operationsof 1315 may be performed according to the methods described herein. Incertain examples, aspects of the operations of 1315 may be performed bya TB-level EDC generator as described with reference to FIGS. 8 through10.

At 1320, the UE 115 or base station 105 may generate a codeword based atleast in part on the plurality of data segments, the CB-level EDCs forthe subset of the plurality of data segments, and the TB-level EDC. Theoperations of 1320 may be performed according to the methods describedherein. In certain examples, aspects of the operations of 1320 may beperformed by a codeword generator as described with reference to FIGS. 8through 10.

At 1325, the UE 115 or base station 105 may transmit the codeword via awireless channel. The operations of 1325 may be performed according tothe methods described herein. In certain examples, aspects of theoperations of 1325 may be performed by a codeword communicator asdescribed with reference to FIGS. 8 through 10.

FIG. 14 shows a flowchart illustrating a method 1400 for reducedoverhead error detection code design for decoding a codeword inaccordance with aspects of the present disclosure. The operations ofmethod 1400 may be implemented by a UE 115 or base station 105 or itscomponents as described herein. For example, the operations of method1400 may be performed by a communications manager 815, 915, and 1015 asdescribed with reference to FIGS. 8 through 10. In some examples, a UE115 or base station 105 may execute a set of codes to control thefunctional elements of the device to perform the functions describedherein. Additionally or alternatively, the UE 115 or base station 105may perform aspects of the functions described herein usingspecial-purpose hardware.

At 1405, the UE 115 or base station 105 may segment a TB into aplurality of data segments. The operations of 1405 may be performedaccording to the methods described herein. In certain examples, aspectsof the operations of 1405 may be performed by a segmentor as describedwith reference to FIGS. 8 through 10.

At 1410, the UE 115 or base station 105 may generate a CB-level EDC foreach data segment of a subset of the plurality of data segments. Theoperations of 1410 may be performed according to the methods describedherein. In certain examples, aspects of the operations of 1410 may beperformed by a CB-level EDC generator as described with reference toFIGS. 8 through 10.

At 1415, the UE 115 or base station 105 may generate a TB-level EDCbased at least in part on the plurality of data segments. The operationsof 1415 may be performed according to the methods described herein. Incertain examples, aspects of the operations of 1415 may be performed bya TB-level EDC generator as described with reference to FIGS. 8 through10.

At 1420, the UE 115 or base station 105 may generate a codeword based atleast in part on the plurality of data segments, the CB-level EDCs forthe subset of the plurality of data segments, and the TB-level EDC. Theoperations of 1420 may be performed according to the methods describedherein. In certain examples, aspects of the operations of 1420 may beperformed by a codeword generator as described with reference to FIGS. 8through 10.

At 1425, the UE 115 or base station 105 may transmit the codeword via awireless channel. The operations of 1425 may be performed according tothe methods described herein. In certain examples, aspects of theoperations of 1425 may be performed by a codeword communicator asdescribed with reference to FIGS. 8 through 10.

At 1430, the UE 115 or base station 105 may receive feedback indicatingthat at least one data segment of the plurality of data segments did notpass error detection. The operations of 1430 may be performed accordingto the methods described herein. In certain examples, aspects of theoperations of 1430 may be performed by a feedback responder as describedwith reference to FIGS. 8 through 10.

At 1435 the UE 115 or base station 105 may generate a second codewordbased at least in part on the at least one data segment. The operationsof 1435 may be performed according to the methods described herein. Incertain examples, aspects of the operations of 1435 may be performed bya feedback responder as described with reference to FIGS. 8 through 10.

At 1440 the UE 115 or base station 105 may transmit the second codewordvia the wireless channel. The operations of 1440 may be performedaccording to the methods described herein. In certain examples, aspectsof the operations of 1440 may be performed by a feedback responder asdescribed with reference to FIGS. 8 through 10.

FIG. 15 shows a flowchart illustrating a method 1500 for reducedoverhead error detection code design for decoding a codeword inaccordance with aspects of the present disclosure. The operations ofmethod 1500 may be implemented by a UE 115 or base station 105 or itscomponents as described herein. For example, the operations of method1500 may be performed by a communications manager 815, 915, and 1015 asdescribed with reference to FIGS. 8 through 10. In some examples, a UE115 or base station 105 may execute a set of codes to control thefunctional elements of the device to perform the functions describedherein. Additionally or alternatively, the UE 115 or base station 105may perform aspects of the functions described herein usingspecial-purpose hardware.

At 1505, the UE 115 or base station 105 may process a signal including acodeword to obtain a candidate bit sequence. The operations of 1505 maybe performed according to the methods described herein. In certainexamples, aspects of the operations of 1505 may be performed by acandidate bit sequence identifier as described with reference to FIGS. 8through 10.

At 1510, the UE 115 or base station 105 may segment the candidate bitsequence into a plurality of CBs that each include a respective datasegment of a plurality of data segments. The operations of 1510 may beperformed according to the methods described herein. In certainexamples, aspects of the operations of 1510 may be performed by acandidate bit sequence segmentor as described with reference to FIGS. 8through 10.

At 1515, the UE 115 or base station 105 may generate a CB-level errordetection determination for each CB of a subset of the plurality of CBs.The operations of 1515 may be performed according to the methodsdescribed herein. In certain examples, aspects of the operations of 1515may be performed by a CB-level error detector as described withreference to FIGS. 8 through 10.

At 1520, the UE 115 or base station 105 may generate a TB-level errordetection determination associated with the plurality of data segments.The operations of 1520 may be performed according to the methodsdescribed herein. In certain examples, aspects of the operations of 1520may be performed by a TB-level error detector as described withreference to FIGS. 8 through 10.

At 1525, the UE 115 or base station 105 may generate an error detectiondetermination associated with the plurality of data segments based atleast in part on the CB-level error detection determinations and theTB-level error detection determination. The operations of 1525 may beperformed according to the methods described herein. In certainexamples, aspects of the operations of 1525 may be performed by a datasegment error detector as described with reference to FIGS. 8 through10.

FIG. 16 shows a flowchart illustrating a method 1600 for reducedoverhead error detection code design for decoding a codeword inaccordance with aspects of the present disclosure. The operations ofmethod 1600 may be implemented by a UE 115 or base station 105 or itscomponents as described herein. For example, the operations of method1600 may be performed by a communications manager 815, 915, and 1015 asdescribed with reference to FIGS. 8 through 10. In some examples, a UE115 or base station 105 may execute a set of codes to control thefunctional elements of the device to perform the functions describedherein. Additionally or alternatively, the UE 115 or base station 105may perform aspects of the functions described herein usingspecial-purpose hardware.

At 1605, the UE 115 or base station 105 may process a signal including acodeword to obtain a candidate bit sequence. The operations of 1605 maybe performed according to the methods described herein. In certainexamples, aspects of the operations of 1605 may be performed by acandidate bit sequence identifier as described with reference to FIGS. 8through 10.

At 1610, the UE 115 or base station 105 may segment the candidate bitsequence into a plurality of CBs that each include a respective datasegment of a plurality of data segments. The operations of 1610 may beperformed according to the methods described herein. In certainexamples, aspects of the operations of 1610 may be performed by acandidate bit sequence segmentor as described with reference to FIGS. 8through 10.

At 1615, the UE 115 or base station 105 may generate a CB-level errordetection determination for each CB of a subset of the plurality of CBs.The operations of 1615 may be performed according to the methodsdescribed herein. In certain examples, aspects of the operations of 1615may be performed by a CB-level error detector as described withreference to FIGS. 8 through 10.

At 1620, the UE 115 or base station 105 may generate a TB-level errordetection determination associated with the plurality of data segments.The operations of 1620 may be performed according to the methodsdescribed herein. In certain examples, aspects of the operations of 1620may be performed by a TB-level error detector as described withreference to FIGS. 8 through 10.

At 1625, the UE 115 or base station 105 may set the TB-level errordetection determination to indicate that an error was identified basedat least in part on determining that at least one of the CB-level errordetection determinations indicate an error. The operations of 1625 maybe performed according to the methods described herein. In certainexamples, aspects of the operations of 1625 may be performed by aTB-level error detector as described with reference to FIGS. 8 through10.

At 1630, the UE 115 or base station 105 may generate an error detectiondetermination associated with the plurality of data segments based atleast in part on the CB-level error detection determinations and theTB-level error detection determination. The operations of 1630 may beperformed according to the methods described herein. In certainexamples, aspects of the operations of 1630 may be performed by a datasegment error detector as described with reference to FIGS. 8 through10.

FIG. 17 shows a flowchart illustrating a method 1700 for reducedoverhead error detection code design for decoding a codeword inaccordance with aspects of the present disclosure. The operations ofmethod 1700 may be implemented by a UE 115 or base station 105 or itscomponents as described herein. For example, the operations of method1700 may be performed by a communications manager 815, 915, and 1015 asdescribed with reference to FIGS. 8 through 10. In some examples, a UE115 or base station 105 may execute a set of codes to control thefunctional elements of the device to perform the functions describedherein. Additionally or alternatively, the UE 115 or base station 105may perform aspects of the functions described herein usingspecial-purpose hardware.

At 1705, the UE 115 or base station 105 may process a signal including acodeword to obtain a candidate bit sequence. The operations of 1705 maybe performed according to the methods described herein. In certainexamples, aspects of the operations of 1705 may be performed bycandidate bit sequence identifier as described with reference to FIGS. 8through 10.

At 1710, the UE 115 or base station 105 may segment the candidate bitsequence into a plurality of CBs that each include a respective datasegment of a plurality of data segments. The operations of 1710 may beperformed according to the methods described herein. In certainexamples, aspects of the operations of 1710 may be performed bycandidate bit sequence segmentor as described with reference to FIGS. 8through 10.

At 1715, the UE 115 or base station 105 may identify a first datasegment of a first CB of the plurality of CBs using a CB-level errordetection code of the first CB. In certain examples, aspects of theoperations of 1715 may be performed by CB-level error detector asdescribed with reference to FIGS. 8 through 10.

At 1720, the UE 115 or base station 105 may identify a second datasegment of a second CB of the plurality of CBs using a CB-level errordetection code of the second CB. The operations of 1720 may be performedaccording to the methods described herein. In certain examples, aspectsof the operations of 1720 may be performed by CB-level error detector asdescribed with reference to FIGS. 8 through 10.

At 1725, the UE 115 or base station 105 may generate a TB by combiningthe first data segment and the second data segment. The operations of1725 may be performed according to the methods described herein. Incertain examples, aspects of the operations of 1725 may be performed byTB-level error detector as described with reference to FIGS. 8 through10.

At 1730, the UE 115 or base station 105 may perform a TB-level errordetection determination of the first data segment and the second datasegment of the TB using a TB-level error detection code. The operationsof 1730 may be performed according to the methods described herein. Incertain examples, aspects of the operations of 1730 may be performed byTB-level error detector as described with reference to FIGS. 8 through10.

It should be noted that the methods described herein describe possibleimplementations, and that the operations and the steps may be rearrangedor otherwise modified and that other implementations are possible.Further, aspects from two or more of the methods may be combined.

Techniques described herein may be used for various wirelesscommunications systems such as code division multiple access (CDMA),time division multiple access (TDMA), frequency division multiple access(FDMA), orthogonal frequency division multiple access (OFDMA), singlecarrier frequency division multiple access (SC-FDMA), and other systems.A CDMA system may implement a radio technology such as CDMA2000,Universal Terrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-2000,IS-95, and IS-856 standards. IS-2000 Releases may be commonly referredto as CDMA2000 1×, 1×, etc. IS-856 (TIA-856) is commonly referred to asCDMA2000 1×EV-DO, High Rate Packet Data (HRPD), etc. UTRA includesWideband CDMA (WCDMA) and other variants of CDMA. A TDMA system mayimplement a radio technology such as Global System for MobileCommunications (GSM).

An OFDMA system may implement a radio technology such as Ultra MobileBroadband (UMB), Evolved UTRA (E-UTRA), Institute of Electrical andElectronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE802.20, Flash-OFDM, etc. UTRA and E-UTRA are part of Universal MobileTelecommunications System (UMTS). LTE and LTE-A are releases of UMTSthat use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, NR, and GSM aredescribed in documents from the organization named “3rd GenerationPartnership Project” (3GPP). CDMA2000 and UMB are described in documentsfrom an organization named “3rd Generation Partnership Project 2”(3GPP2). The techniques described herein may be used for the systems andradio technologies mentioned above as well as other systems and radiotechnologies. While aspects of an LTE or an NR system may be describedfor purposes of example, and LTE or NR terminology may be used in muchof the description, the techniques described herein are applicablebeyond LTE or NR applications.

A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEs115 with service subscriptions with the network provider. A small cellmay be associated with a lower-powered base station 105, as comparedwith a macro cell, and a small cell may operate in the same or different(e.g., licensed, unlicensed, etc.) frequency bands as macro cells. Smallcells may include pico cells, femto cells, and micro cells according tovarious examples. A pico cell, for example, may cover a small geographicarea and may allow unrestricted access by UEs 115 with servicesubscriptions with the network provider. A femto cell may also cover asmall geographic area (e.g., a home) and may provide restricted accessby UEs 115 having an association with the femto cell (e.g., UEs 115 in aclosed subscriber group (CSG), UEs 115 for users in the home, and thelike). An eNB for a macro cell may be referred to as a macro eNB. An eNBfor a small cell may be referred to as a small cell eNB, a pico eNB, afemto eNB, or a home eNB. An eNB may support one or multiple (e.g., two,three, four, and the like) cells, and may also support communicationsusing one or multiple component carriers.

The wireless communications system 100 or systems described herein maysupport synchronous or asynchronous operation. For synchronousoperation, the base stations 105 may have similar frame timing, andtransmissions from different base stations 105 may be approximatelyaligned in time. For asynchronous operation, the base stations 105 mayhave different frame timing, and transmissions from different basestations 105 may not be aligned in time. The techniques described hereinmay be used for either synchronous or asynchronous operations.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the above description may berepresented by voltages, currents, electromagnetic waves, magneticfields or particles, optical fields or particles, or any combinationthereof

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a digital signal processor (DSP), anapplication-specific integrated circuit (ASIC), a field-programmablegate array (FPGA) or other programmable logic device (PLD), discretegate or transistor logic, discrete hardware components, or anycombination thereof designed to perform the functions described herein.A general-purpose processor may be a microprocessor, but in thealternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices (e.g., a combinationof a DSP and a microprocessor, multiple microprocessors, one or moremicroprocessors in conjunction with a DSP core, or any other suchconfiguration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described herein can be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations.

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that can beaccessed by a general purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media mayinclude random-access memory (RAM), read-only memory (ROM), electricallyerasable programmable read only memory (EEPROM), flash memory, compactdisk (CD) ROM or other optical disk storage, magnetic disk storage orother magnetic storage devices, or any other non-transitory medium thatcan be used to carry or store desired program code means in the form ofinstructions or data structures and that can be accessed by ageneral-purpose or special-purpose computer, or a general-purpose orspecial-purpose processor. Also, any connection is properly termed acomputer-readable medium. For example, if the software is transmittedfrom a website, server, or other remote source using a coaxial cable,fiber optic cable, twisted pair, digital subscriber line (DSL), orwireless technologies such as infrared, radio, and microwave, then thecoaxial cable, fiber optic cable, twisted pair, DSL, or wirelesstechnologies such as infrared, radio, and microwave are included in thedefinition of medium. Disk and disc, as used herein, include CD, laserdisc, optical disc, digital versatile disc (DVD), floppy disk andBlu-ray disc where disks usually reproduce data magnetically, whilediscs reproduce data optically with lasers. Combinations of the aboveare also included within the scope of computer-readable media.

As used herein, including in the claims, “or” as used in a list of items(e.g., a list of items prefaced by a phrase such as “at least one of” or“one or more of”) indicates an inclusive list such that, for example, alist of at least one of A, B, or C means A or B or C or AB or AC or BCor ABC (i.e., A and B and C). Also, as used herein, the phrase “basedon” shall not be construed as a reference to a closed set of conditions.For example, an exemplary step that is described as “based on conditionA” may be based on both a condition A and a condition B withoutdeparting from the scope of the present disclosure. In other words, asused herein, the phrase “based on” shall be construed in the same manneras the phrase “based at least in part on.”

In the appended figures, similar components or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label, or othersubsequent reference label.

The description set forth herein, in connection with the appendeddrawings, describes example configurations and does not represent allthe examples that may be implemented or that are within the scope of theclaims. The term “exemplary” used herein means “serving as an example,instance, or illustration,” and not “preferred” or “advantageous overother examples.” The detailed description includes specific details forthe purpose of providing an understanding of the described techniques.These techniques, however, may be practiced without these specificdetails. In some instances, well-known structures and devices are shownin block diagram form in order to avoid obscuring the concepts of thedescribed examples.

The description herein is provided to enable a person skilled in the artto make or use the disclosure. Various modifications to the disclosurewill be readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other variations withoutdeparting from the scope of the disclosure. Thus, the disclosure is notlimited to the examples and designs described herein, but is to beaccorded the broadest scope consistent with the principles and novelfeatures disclosed herein.

1. (canceled)
 2. A method for wireless communication, comprising:segmenting control information into a first segment and a secondsegment, wherein a number of information bits of the first segment isdifferent from a number of information bits of the second segment;generating a first error detection code (EDC) for the first segmentincluding a first number of error detection bits; and generating asecond EDC for the second segment comprising a second number of errordetection bits different from the first number of error detection bits;polar encoding the first segment, the first EDC, the second segment, andthe second EDC; and transmitting a codeword based at least in part onthe polar encoding via a wireless channel.
 3. The method of claim 2,further comprising: associating the first segment with a first codeblock; and associating the second segment with a second code block. 4.The method of claim 3, wherein the codeword comprises the first codeblock, the second code block, and at least one other code block.
 5. Themethod of claim 2, further comprising: receiving feedback indicatingwhether the first segment and the second segment passed error detection;and processing a sequence of bits included in the feedback to determinewhether one or both of the first segment and the second segment passederror detection.
 6. The method of claim 2, further comprising: receivingfeedback indicating that at least one segment of the first segment andthe second segment did not pass error detection; generating a secondcodeword based at least in part on the at least one segment; andtransmitting the second codeword via the wireless channel.
 7. The methodof claim 2, wherein each of the first EDC and the second EDC is a codeblock-level EDC.
 8. The method of claim 2, wherein each of the first EDCand the second EDC is a cyclic redundancy check (CRC).
 9. A method forwireless communication, comprising: processing a signal comprising acodeword to obtain a candidate bit sequence; segmenting the candidatebit sequence into a first code block and a second code block;identifying a first segment comprising a first number of informationbits of the first code block using a first error detection code (EDC)comprising a first number of error detection bits; identifying a secondsegment comprising a second number of information bits different fromthe first number of information bits of the second code block using asecond EDC comprising a second number of error detection bits differentfrom the first number of error detection bits; and generating controldata from the first segment and the second segment.
 10. The method ofclaim 9, further comprising: determining that the first segment and thesecond segment passed error detection based at least in part ondetermining that error detection determinations associated with thefirst code block and the second code block do not indicate an error. 11.The method of claim 9, further comprising: transmitting feedbackindicating that at least one of the first segment and the second segmentdid not pass error detection based at least in part on error detectiondeterminations associated with the first code block and the second codeblock.
 12. The method of claim 9, wherein processing the signalcomprising the codeword to obtain the candidate bit sequence comprises:performing a list decoding algorithm to decode the codeword according toa polar code to generate the candidate bit sequence.
 13. The method ofclaim 9, further comprising: generating a first calculated EDC for thefirst segment; obtaining a first received EDC from the first code block;and comparing the first calculated EDC and the first received EDC,wherein error detection determination for the first code block indicateswhether the first calculated EDC matches the first received EDC.
 14. Anapparatus for wireless communication, comprising: a processor; andmemory coupled with the processor and storing instructions executable bythe processor to cause the apparatus to: segment control informationinto a first segment and a second segment, wherein a number ofinformation bits of the first segment is different from a number ofinformation bits of the second segment; generate a first error detectioncode (EDC) for the first segment including a first number of errordetection bits; generate a second EDC for the second segment comprisinga second number of error detection bits different from the first numberof error detection bits; polar encode the first segment, the first EDC,the second segment, and the second EDC; and transmit a codeword based atleast in part on the polar encoding via a wireless channel.
 15. Theapparatus of claim 14, wherein the instructions are further executableby the processor to cause the apparatus to: associate the first segmentwith a first code block; and associate the second segment with a secondcode block.
 16. The apparatus of claim 15, wherein the codewordcomprises the first code block, the second code block, and at least oneother code block.
 17. The apparatus of claim 14, wherein theinstructions are further executable by the processor to cause theapparatus to: receive feedback indicating whether the first segment andthe second segment passed error detection; and process a sequence ofbits included in the feedback to determine whether one or both of thefirst segment and the second segment passed error detection.
 18. Theapparatus of claim 14, wherein the instructions are further executableby the processor to cause the apparatus to: receive feedback indicatingthat at least one segment of the first segment and the second segmentdid not pass error detection; generate a second codeword based at leastin part on the at least one segment; and transmit the second codewordvia the wireless channel.
 19. The apparatus of claim 14, wherein each ofthe first EDC and the second EDC is a code block-level EDC.
 20. Theapparatus of claim 14, wherein each of the first EDC and the second EDCis a cyclic redundancy check (CRC).
 21. An apparatus for wirelesscommunication, comprising: a processor; and memory coupled with theprocessor and storing instructions executable by the processor to causethe apparatus to: process a signal comprising a codeword to obtain acandidate bit sequence; segment the candidate bit sequence into a firstcode block and a second code block; identify a first segment comprisinga first number of information bits of the first code block using a firsterror detection code (EDC) comprising a first number of error detectionbits; identify a second segment comprising a second number ofinformation bits different from the first number of information bits ofthe second code block using a second EDC comprising a second number oferror detection bits different from the first number of error detectionbits; and generate control data from the first segment and the secondsegment.
 22. The apparatus of claim 21, wherein the instructions arefurther executable by the processor to cause the apparatus to: determinethat the first segment and the second segment passed error detectionbased at least in part on determining that error detectiondeterminations associated with the first code block and the second codeblock do not indicate an error.
 23. The apparatus of claim 21, whereinthe instructions are further executable by the processor to cause theapparatus to: transmit feedback indicating that at least one of thefirst segment and the second segment did not pass error detection basedat least in part on error detection determinations associated with thefirst code block and the second code block.
 24. The apparatus of claim21, wherein the instructions to process the signal comprising thecodeword are executable by the processor to cause the apparatus to:perform a list decoding algorithm to decode the codeword according to apolar code to generate the candidate bit sequence.
 25. The apparatus ofclaim 21, wherein the instructions are further executable by theprocessor to cause the apparatus to: generate a first calculated EDC forthe first segment; obtain a first received EDC from the first codeblock; and compare the first calculated EDC and the first received EDC,wherein error detection determination for the first code block indicateswhether the first calculated EDC matches the first received EDC.